That's what I've been told, too - that the Kaiten removal has something to do with making future changes easier.
This makes me more nervous than I was - so it isn't just about button bloat, but a general direction. For that reason, among others, I think it's really important to keep at this, because it is reminding me unfavorably of other mmos I've played (I started ff in '16, so before that) - when the direction went from choice & talent trees with meaningful choices there, too, to an exceptionally bland, easy-for-all blob. Personally, I'd prefer MORE choices in my classes. I think the class I've liked best in any mmo was the old Burglar in LOTRO - it was feeble and slow but I had to make a choice with every hit, and I loved that. I'm not expecting that, or asking for it, but I surely do not want this game to go in the other direction, so that a lovely flowing class like the Samurai *was* becomes dull and boring.