I understand where this sentiment comes from, but I also feel like it is just an incredibly misguided mindset to have with RPGs on the whole. You will typically know if a game will be to your liking within the first 2-3 hours at most. Either the early combat concepts, story setup and characters grab you or they don't. If anyone said this sort of thing about a novel it would be laughable.
It is true that some RPG climaxes are controversial, but even then, I think people who decide to hate a 20+ hour journey just because the last 3-5 or so hours disappointed them are being silly. It is rational, since the last thing we experience in a game will be what sticks with us, but as I've grown older I like to think I've gotten pretty good at keeping my vibes positive with a game even if I disliked the ending of a 40+ hour long JRPG.
The genre isn't for everyone and that's ok. Length can be daunting, but much like long-running franchises like One Piece I like to highlight that the journey is far more important than the destination. If you aren't enjoying the journey than don't take it, but don't let the length of the journey stop you from even trying to take the first step, especially if you think you'd enjoy the experience.