The Vita was completely different. Games were made on a completely different platform with very different architechture, from scratch basically, and Sony didn't give it the support it needed to succeed. A modern Vita with it's similar architecture would benefit from easy and immediate ports from 1st and 3rd party (part of the reason switch has been successful)
It also wasn't a hybrid, which the the Vita 2 would be. (and also another huge reason the switch was successful) So it's apples to oranges.
As to nobody else doing numbers like nintendo in the portable space, name me one portable machine that had a proper game company behind it in the past 10 years? You can't.
Even the Steam Deck doesn't count as it doesn't have console exclusives nor does it have enough stock built to even matter.
As to Sony reaching out to a market that the rest didn't even see, that's not true either. MS saw it, said it was too small, and they were 100% right. 5 million units of an add for a machine that sold over a 100 million is a failure on an epic scale.
The PSVR2 has some amazing tech in it, I will buy it and enjoy it, but how many units do you think they can sell for a console that has sold 20 million units?
Best in class? Maybe, for a year or 2, then not so much. A lot of people hate being tethered for VR. There are competitors in this space who won't sit on their hands.
We do know that PSVR exists, we have no idea if Vita is being worked on. To me the PSVR seems more of a passion project for Sony than a way to increase market share or profit. (and good for us, not for them)
The poll results here seem to indicate Vita, and these are hardcore gamers, the type who tend to gravitate to VR. The poll would lean even more to vita for casual gamers as more as a percentage are not interested in VR.