I've seen gameplay videos and read reviews. Nothing the company has done for quite some time has interested me, except Bravely Default. But I lack a 3DS, so I haven't played that either.
XIII-2 might have been a very good game, but the problem is, to properly understand it, you'll have to have played XIII, and that's an experience that a lot of people simply have no desire to go through.
Crisis Core seems to have been the only part of the Compilation that wasn't universally hated, but even then, it hasn't gotten anywhere near as glowing reviews as the games from Square's heyday. The general consensus seems to be "It's a passable game, but nowhere near as good as the original, and Genesis is a terrible character". And since the original didn't bowl me over that much in the first place, I don't really see any need to play a prequel.
I'm well aware that the relaunch of XIV has been quite successful, but the fact that Square Enix botched the initial launch as badly as they did does not inspire confidence that their future products will be good. We can't expect that they'll have the opportunity to revamp their future games as they did XIV.
I've been a fan of the series since before X came out and I haven't seen any game in the series be as widely reviled as XIII. Yes, it still has its defenders, but there are nowhere near as many of them as there are for any other games in the series (at least since maybe II).