Actually you can do that, and they did (as proof). Much like most other games that are released on pre-order for 30 years, long before the system requirements are known. This isn't the first time or even unusual, it is common practice since the beginning of time.

Nobody is forced to buy it. If someone is worried about it, don't buy it. Or buy it and later when the system requirements are known, they can get a refund if it wont run on their system. I'm sure they wouldn't have a problem with that since they're asking for money right now and are a generally fair and consumer friendly company, not to mention it's probably required by law in various countries and they're unlikely to do it only for some customers in certain countries.

You can actually ask for money for a game 8-10 years before you even release a game, without people even knowing what the game is ever going to end up being, and a decade before the system requirements are known with certainty. As a proof of this, Star Citizen was announced eons ago and uses crowd funding for people to essentially "pre-order" the game for many years now, is still in heavy development alpha with not even a beta anywhere in sight let alone a release date, and not even the slightest hint of what the system requirements will ever be. They've raised 227 million dollars in funding so far, and growing. Perfectly legal, and $227 million worth of people's money have voted to say "this is ok to us, we're willing to buy now and maybe get the game at some unknown date that could be years or decades away maybe, and it might not run on our computers."

https://robertsspaceindustries.com/funding-goals

Cyberpunk 2077 not listing currently unknown system requirements is not only not unexpected this long before the game launches, it's actually totally expected - at least by anyone who has followed lots of games development cycles over time or whom is a develojper themselves. I'm willing to bet that huge droves of people are so excited by the game nearing completion that the overwhelming majority are buying now and not worrying about whether the game will run on their computers later, and that the rest is just line noise.

Don't get me wrong though, I wouldn't buy a game in advance without knowing or feeling rather confident that it would run on my system either, but if I could not get that guarantee or reasonable speculation then I would assume that it would not run and not buy it until I knew it could run - either by future information, or by getting a more powerful computer along the way.

Yeah, some people will miss out on whatever pre-order bonus features there are short term, but that's the lottery ticket. And there's always future refunds unless they say no to that for some reason. Either way, we're not going to get system requirements until they actually know themselves what they'll be, and if they did know that there would be absolutely no good reason for them to not tell us, it'd be in their own best interest to share this information with people as soon as they possibly can. There's no benefit of keeping such information a secret, it doesn't help them in any way if they know the answer.

The only sensible conclusion can be that they do not know, and thus can not say. Anything else would merely be conspiracy theory, and I'm sure there will be some of that out there too, as par for the course. They're providing a special offer to people who know or are willing to risk it for the time being, without a gun to anyone's head.

It's all good though one way or another. It all generates more hype and talk about the game, and more sales.

More importantly (to me anyway), is it's all good funding for the development of The Witcher 4. :)