xxspe: Ahah of course not! But imagine: you start an indie studio and you love making/playing platformer. Are we going to force ourself making another roguelike-pixel art-zombie-crafting game? Not really... It's about principles and knowning one's strenghs. Yes puzzle platformers are saturated and we need to be excellent to stand out. What comes out of the post mortem is 1) nobody knew about Ethan = we need to change the way we market our games AND choose a better release window, 2) game looks unappealing / without soul = we'll do less levels and work more on making the art unique and story exciting.
Wishbone: Yes, those two points were made by lots of people, but the one point made by almost everybody was "Don't make yet another indie puzzle platformer!" If you choose to ignore that, then... And nobody is asking you to make "another roguelike-pixel art-zombie-crafting game". The whole point about not making another puzzle platformer is that there are too many of the already. Switching to another genre which is just as saturated would make just as little sense. You need to be original. Make a kind of game that the market is not already flooded with. Try to be just a little bit creative, instead of just churning out the same formula that others have done thousands of times before. The one thing indie developers have going for them is that they don't have publisher executives dictating what kind of games they should make, so they don't have to stick to the tried-and-true approach. Throwing that away means throwing away the one thing you have going for you.
Originality is welcome but isn't necessarily an inherently good thing. Trespasser, the Jurassic Park game, was WILDLY original in many of the things it did but failed at practically all of them and has now become infamous for that reason. Jason Rohrer and Tale of Tales games are also pretty original too but in ways that I would neither consider fun to play or even playable. I think making a game that is "good" should be the prime directive of every developer. Maybe the problem isn't that there are too many indie puzzle-platformers, but not enough good ones? I've not played Ethan so I wouldn't know, the failure here it seems to me would be a matter of marketing and choice of aesthetic than the gameplay, since, as it sold so poorly, most of us can't really say one way or another about it.
If the dev says they love making platformers and will continue to do so then that's great, let them do so. Doing what you love is more important than forcing yourself to do something you don't in any case. And making something more original isn't a bonafide guarantee for ultimate (financial) success either. Face it, the indie market
in general is heavily saturated. Good self-promotion, good word-of-mouth and screenshots and/or a premise that'll grab people's attention are the best chances for success but in the end it's always about luck above all else. Let's look at another indie title that went "post-mortem," that one being Retro/Grade. Read about that game, now THERE'S a game that nobody could accuse of being unoriginal. Basically it's a kind of rhythm game at heart but in the guise of a shmup being played in reverse. According to the dev, it bombed, and he fell into a depression as a result. Right now though he's working on a kind of survival horror/adventure game called Neverending Nightmare which was a success on Kickstarter and slated for release the middle of next year. It's definitely not as original-looking as Retro/Grade but did get good wide-spread word-of-mouth from renowned YouTubers and such from its demo and has a cool aesthetic going for it, plus an interesting premise having to do with the dev's personal struggles with clinical depression and OCD. A combination of those factors definitely helped in reaching (actually exceeding) its Kickstarter goal though there was a point where it seemed like it wouldn't make it, yet like so many Kickstarters, most people kicked in at the final hour and now we have an interesting-looking game being made as a result. However not everyone is so lucky, the next great developer with the next amazing concept and subsequent amazing game is probably unknown to all of us, wasting away with three supporters and few hundred dollars at the bottom of an IndieGoGo campaign and to be forever mired in shadow or obsolescence.
In the end, making a game that is both complete and good should always be the prime motivating factor, same goes for anyone writing a book, making a film, making music, etc. if nobody buys it, blame the devs for not doing something "more original" or the public for failing to take notice, either way at least you have your work out there for anyone willing to take notice and if indeed it IS good it will find its audience, even if it's a small one.
So no, discouraging the developer from making platformers is not the way to go, rather encouraging them to do something with the genre they enjoy making games of that will catch people's attention if that's what they're after.