Final Fantasy VIII does get quite alot of hate and backlash, but Final Fantasy V and Final Fantasy III basically have not much of a fanbase whatsoever same with Final Fantasy II.

Final Fantasy II basically not there at all, it's either extremely hated or not played at all. You would have a better chance of finding a fan of one of those obscure Mario games like Mario is Missing.

Final Fantasy III I've seen like one fan online, that's it. Same with Final Fantasy V.

Final Fantasy VIII does have a small fanbase but it's not like it's bare bones like some of the earlier FF titles.

Underated ? Yes. Hated by a few ? Yes. But extremely thirsty for fans. Nope.