FFT is a game I have played through 3+ times with probably 1,000+ total playtime and I’ve played all the games you mention. I recommended FFT to a friend a few years ago and watched him play through the first couple missions and it’s easy to forget the difficulty curve of that game if you haven’t played an older style TRPG. A lot of the mechanics aren’t really explained well (stat growth for example), there’s permadeath, a few instances of possible softlocking, and a bunch of really obscure requirements to access some of the content and recruit some of the characters.
I think it suffers from sequel syndrome where the newer TRPGs have better quality of life aspects to them. That said there are rumors of a remake that maybe will address some of that.