I mean, yes, virtually all boss fights in all JRPGs will come down to that, but compare FFXIII's pressing two buttons to, say, a SMT boss.
See, the thing was, you could say that about the FF series in 98% of its boss fights. Very rarely do FF games typically require strategy or particularly prompt attention except in the most edge cases; otherwise you can get away with spamming attack. I mean, arguably, SMT boss fights come down to "spam buff/debuff and then just wail on it" as well, but generally this qualifies as acceptable levels of strategy for an RPG.
One of the reasons FFXII worked for people wasn't just because the gambits let you set things up to flow nicely; it was because the game was fast-paced enough that you couldn't really
afford to spend all that time telling every ally exactly what to do for every action (Active on full speed is particularly challenging for this reason; setting up your Gambits incorrectly leads to you desperately trying to keep up with your party's mistakes).
For FFXIII, yes, arguably it is more barebones. Mostly because it cut out a whole lot of redundancies, I find; but also because it needed to be. Yeah, it sorta makes standard encounters feel somewhat boring - this was the same issue Gambits created in XII, was that a regular fight was pretty much on automatic and you didn't have to do much, and for
most of XIII yeah, I'll admit, it feels the same. But dem boss battles. Yes, there's no way to cheese or zerg rush (most) of them, but I kind of like that. You actually have to use the tools available to you, and dawdling on your decision making for even a second in many can be death, and that's honestly why I loved it. The fact that, later on, more and more regular battles are potentially life threatening if you approach them the wrong way or overconfidently too is great to me.
Then again, I'm still riding high from the last time I did the game's final chapters. And that might be blinding me to how monotonous getting through the earlier game can be, since pretty much every fight from
onwards in the game is a boss fight, even the seeming non-boss encounters, and it's one of the most active, fun, and difficult final stretches of an RPG in my memory. Generally by the end of a game you're either so overpowered that you roflstomp everything or you're simply better of running from every encounter because they're all full of bullshit. XIII had the rare endgame where I found neither to be the case and was where the game really shone, instead of dragging out the final area like most RPGs end up feeling ("oh god why the hell isn't this dungeon over yet I just want to be done")
