Yes, you can.not gonna reply to everything individually (can you even do that in the same post?)
To me, what instantly turns me off a game is when it's one of those massive, 40+ hour games, especially when it has a lot of grinding.I think the perception on this is just warped since as kids and teenagers you have far more time, so being stuck on a certain part of a game for days if not weeks was not an issue. I remember never getting past 50 Stars in Mario 64 before I turned 10, yet at 13 I 100%ed it because I became more involved with gaming in general. (also experience making me better at playing) You have more time, less games, and in a lot of cases (Pokemon especially) a friendship network where you exchange on how to progress at certain parts.
Nowadays I get frustrated when I'm stuck for more than half an hour (Edit note: very much not true for Pokemon), and often catch myself looking up little stuff, especially in older RPGs (also missables) because the time I can spent has simply been cut down by having to work and do annoying "adult" stuff. (being more experienced also means I never really get completely stuck so I guess it balances itself out a bit at least...) NES era games tend to be a lot more unforgiving in terms of obscure design (the first 2 Zeldas are generally seen as guide games), but I do think it persisted in lesser form in some way (though mostly optional, as being mentioned by others above)
I already work too much to have a hobby that requires tedious padding.