Horses for courses. I much prefer FF7 combat system than any other final fantasy game. FF8 and 9 were not too bad either as I recall, but not replayed those so it has been about two decades now
Getting old
FF9 system wasn't a problem (though weakest of all 3), it was just so slow - as in it felt like it took minutes to actually start combat once an encounter was triggered.
FF7 Materia system was good, though replaying the game I found myself obsessively moving them around to max them out rather than truly playing a character with them which I think may have been why I did not enjoy FFVII as much as when I was younger and likely just blundering around back then. I also hated situations where you were forced to take chars who otherwise you never used, so they sucked
FFX I liked the spheres and I liked the fact I could swap chars during combat. Gearing in it sucked though - there was no 'loot excitement' which was the games big weakness. I think it was designing the chars that had me enjoying it more than I remembered from the past.
Don't get me wrong, I played the heck out of all 3 of these games since I bought them on the Switch, just interesting to see that X was disappointing to you when for me it was a surprise improvement over my memory. Then again, maybe that's the trick - 7 had been my favorite and was not as great as I remembered