Games in the 80's/90's came with in-depth manuals.

But as of the 2000's, they stopped making manuals, because they decided to: a) be lazy and also b) to cheap out.

So, the lack of manuals necessitated the need for in-game tutorials.

...

I must disagree with this.

Development of in-game tutorials is more costly and time consumers and easier to fail at than a manual.

The move to ingame tutorials was a result of the market.
Games which had good manual and good ingame tutorials were praised for the ingame tutorials.
More and more Games started to use it and it became standard and something people expect to have in game.
That replaced the need for manuals which especially in digital age are no longer necessary.

Ingame tutorials are better than manuals as it allows people to jump into rhe game without needing to do some dry reading. It is preferable method of teaching player about the game over requiring to read chapters in the manual


Edit.

Can we be provided by OP on mandatory tutorials which cannot be skipped and are longer than few minutes.

Actually, that corresponds with a complete lack of literacy that started happening near the end of the 90's, which is why RTFM emerged. Illiterates, who hated being told to read something, now can claim there is no fuck'n manual. But even the manuals of the 80's / 90's were written for people as dumb as modern day humans.

1. Back then people already complained if games were too difficult or complicated. But they complained to their close circle of friends, not to thousands of strangers on the internet from all corners of the world who in return can amplify their own complaints.

2. Nowadays lots more games released every day and relatively cheaper too, so games are more 'disposable'. If it's too difficult, you complain, refund/resell the game, and move on to the next game. Back then if the game's too difficult, you put up and shut up and play the game anyway, trying to make the best of a worst situation, because that's the only new game you have till Christmas or your birthday.

3. Smart people and stupid people always exist in every decade. Using IQ as a yardstick, there's always 50% of people who have above-average intelligence and 50% who have below-average. Back then you might turn a profit selling AAA games to a niche of smart people, but nowadays AAA games are very expensive to produce and publishers are greedier than ever. So if you want to create a popular AAA game, you have to target a wide range of demographics, including people with a wide range of intelligence levels.

4. In the 80s/90s, parents were already complaining "my child becomes stupid, lazy, and disobedient at school because of your video game, shame on you for peddling this satanic tool that poisons our children's future." Parents complaining about no basic tutorials seem like an improvement.

5. Yeah I agree that mandatory tutorial is bad, at the very least give me an option to skip it. I recall there are some modern games that ask you politely at the beginning: Is this your first time playing FPS? Is this your first time playing this particular game? And tailor their tutorial from your familiarity with the game/franchise/genre.

Because they were not dummied down by social media.

yep
+
mostly smart people used the pc-s

in game tutorials are fine, you have to learn at least the controls, it is like going throu the keybindings for the game interactively think so
especially as we can see how game journos are complete noobs, some hardly even finish simple tutorials :O
and then they give low ratings to the game as it is too hard for them
the casual and lately story difficulties are a direct result of this, i bet some games even have autoplay feature now

Progress is always about two steps forward and one back.

Back in the 80s/90s gamers were more like nerds, nowadays almost everyone dabbles in games at some time or other. So the larger demographic has changed, and often they are not very tech savvy, and while they do need a bit of hand holding, you can blame Microsoft and Apple for dumbing everyone down. Hell, even Firefox and others treat us all like dummies now, taking more and more choice away from us ... for our own good ... so they say.

Pretty soon you will need permission from an app on your phone or dumb watch, to go to the toilet.

At some point not too far away, people who think for themselves will be sent to certain countries for corrective treatments.

Could you have even imagined playing a game on your phone back in the 80s/90s ... gawd, who had a mobile phone back then .... more like a lucky few had a brick they talked to other people with bricks.

Also, back then gamers were more inclined to invest more time and learn by trial and error, because they didn't have backlogs with hundreds of games and when you got a new one, you had to make the most out of it.

That was also the time when companies made games difficult to profit on pay per minute help lines, because finding walkthroughs on the internet was a much harder proposition.

To me it is more about convenience, than being dumb or smart or even both.

Sure I could keep drawing maze maps to graph paper and writing down quest logs to my notebook while playing old-skool RPGs... but why would I want to do that nowadays when games have automaps and quest logs which keep track of your progress?

I never really liked having to read a manual in order to learn to play a game. I sometimes did because I used to like flight (combat) simulators a lot, but I did it because I had to, not because I wanted to. I already had to study at school every day, why would I want to study games at home? I generally like tutorials in games, but even more I prefer the game slowly teaches you how to play as you progress, without any separate tutorial. E.g. the original Starcraft was good in doing that, starting with simpler and more relaxed missions, and moving on to somewhat more complex setups.

Also in general... I am not really sure if games have become simpler overtime. Maybe it depends on genre, but when I think about e.g. real-time strategy games, over time they just seemed to become more and more complicated, compared to Dune 2, Warcraft 1-2 etc.

Also old-skool FPS games seem much simpler and straightforward than today's "FPS"-games which are quite often some kind of RPG-lites with a vast open world where you have lots of stuff to do and research.

I don’t know about that. I do feel the 80s and 90s was a happier time. Everyone is so angry, factionalised, and probably spoilt if truth be told. The rise of technology has been so quick and pervasive.

But then there is also a large dollop of the lit was all better in my day” as well, which on an individual level is probably true, I.e. before I was young and the future had hope.

So where the point lies exactly is not black and white.

The reason PC gamers aren't as intelligent right now should be obvious. Think about which types of people were more likely to own home computers in the 1980's and the early parts of the 1990's: professionals. And computer programmers in particular. Skillled, educated, and intelligent people who likely needed them for their science/engineering/programming work (I consider these terms to cover programming). And these were people with REAL educations too... probably computer science or something like that. Not gender studies or something similar.

Computers used to be relatively uncommon and expensive in these days, so the people who could afford them tended to be smarter people who made more money so they could afford them, and people who needed them for work-related tasks (programmers, computer scientists). So, basically, smart people who had more money because they were smart.

Compare that with the typical PC user today. Computer ownership has become common in society, so all the lower classes have them now.

PC game quality has declined accordingly, because developers have to appeal to the lowest common denominator to increase sales.

This is why things that are good often start out as niche communities of elites, and then turn to garbage as they become more mainstream.

agree with that
today buy game and already start for looking a new one before you even start , at least this is what i see what most people do , oh and they will write a review how it is a very good game and playtime shows 1.1hr(0hr in last two weeks) pretty much gives away how much their reviews worth