People who say it had a bad library must not be Switch owners. The switch is getting a lot of the same games and same kind of game Vita got from 3rd parties. A number of them are direct ports. Others are remakes of Vita games. Vita had a good library, it just didn't have that 1st party support Switch has. It did lack those killer 1st party games. Still a good system for RPGs. Some action games. Shooters. Shmups and indies and yes also Visual Novels
I must have missed when Vita got Skyrim, Crash N. Sane Trilogy, Crash Nitro Fuel, DOOM, Wolfenstein, Dragon Quest 11, Snake Pass, etc. I get a lot of those games came out after the Vita was relevant, and there are a number of titles which were on the Vita but weren't good ports (like for example Borderlands 2), but the point still stands. It's a little silly to act like Vita had some really good library comparable to the Switch, then to explain later on that it had a lack of killer first party titles. Ok ... then it didn't have a comparable library? Even if we're just talking third party, there's a number of reasons why the third party on the Switch is more attractive than that on the Vita. Even putting aside major third party exclusives, the Switch's third party games are just generally bigger and more successful. Especially because they emulate consoles much more closely (which is important for games like Borderlands). Also, good first party titles kind of act as a gateway for consoles, especially handhelds where bigger publishers (especially western ones) and bigger games from said publishers are not coming out right out of the gate.
Like sure, you have a lot of the same genres that are popular on both systems, and you even have a lot of junk on the Switch, but that doesn't particularly matter because it doesn't answer what games are on the system, which is more important than just a broad generalization of what kind of games are on it.. And coincidentally a lot of the best selling third party games are in genres that the Vita didn't cover or didn't cover well. So in conclusion, it's really not a jump in logic to say that the Vita has a bad library, but the Switch doesn't. There are a number of very valid reasons that could lead to such a conclusion.