I wouldn't say it is revisionist history at all. Day one people were heavily critical of XIII. It reviewed well, but those reviews had a lot of people raising their eyebrows. The buzz was very negative. I was a huge fan of Final Fantasy and didn't buy it at launch because of how negative the general perception was. When I did eventually get around to playing it, I actually disagreed with one of the most common critiques (that the battle engine was awful), but people were spot on with the rest; that game is a tremendous mess. It deserves its reputation, and it is a reputation that it has had since day one.
XV is largely the same. It has been a divisive game since launch. Though I think a lot of people saw it at the time, and still see it, as being a step in the right direction... because XIII is a very bad game.
Guess we'll just have to agree to disagree, then! I respect your opinion for sure and I'm more than happy to admit FF XIII's flaws, but I think what it did right far overshadowed what it did wrong, and I had an amazing time with it (except for most of the Gran Pulse segment). In no way do I think it's even close to a bad game, let alone "very bad."
And by revisionist history, I mean not only the positive critical reception you mentioned (which can't be discounted just because you or "a lot of people" didn't agree with them) but also its very strong sales as well as the objectively and uniquely lasting impact it has had on the wider FF series, with Lightning becoming one of the faces of the franchise and a fan-favorite character in her own right, regardless of how the FF XIII haters feel about her.
Another important point the anti-FF XIII crowd tends to overlook is that it's far from the first FF that has been strictly linear (not that linearity is a bad thing and I in fact think it's a wonderful thing, but that's a whole different conversation). The real problem is that older FF games were much better at presenting the illusion they were linear when they were, in fact, not (mostly). Where can you go after you leave Baron in FF IV? The cave to Mist. Then Mist. Then the desert, etc. Your choices are incredibly limited. FF VII's Midgar segment? Entirely linear, and once you get to the world map, you can go to three places: Kalm, the Chocobo farm, and the Midgar Zolom fight. Only one advances the story, and the other is an instant Game Over for most low-level parties. Again, linear, but the world map helps present the illusion that it isn't. There are exceptions, of course; FF VI's back half is the most obvious example here, being almost completely non-linear, and FF XII is sometimes/sort of nonlinear to a degree (though I highly dislike XII and never finished it, so if it goes completely nonlinear toward the end, I wouldn't know).
Anyway! I'm not trying to convince you you're wrong about FF XIII, because I know I can't and as with most things, that's entirely subjective. If your gaming tastes lead you to feel it's a bad game, then yeah, it's a bad game for you and you would probably review it as such. The exact opposite goes for me, though -- like I said, I recognize its flaws but am easily able to accept and move past them in light of everything else I think the game excels at.
Either way, thanks for the response! I appreciate the conversation. :)