My opinion actually isn't far off from yours. What a lot of people get wrong is that Nintendo has to go to its knees and beg the 3rd party developers to please, please release titles for their console. Although, it's true that (from reading interviews with 3rd parties) Nintendo has become more amicable to work with (probably since Iwata Satoru became President), even at its weakest stage (WiiU + 3DS era), Nintendo was never in a position where they had to beg to 3rd parties. Nintendo is financially too strong to weather out a weak or even two successive weak generations. With their strong IP's they simply have enough self-confidence that eventually they will be successful again.
What I quoted above from Rol is also my stand: The Switch 2 will (likely) have the technology to port AAA-3rd party games and they will likely be (much) easier to port than it was the case for Switch 1. It's up to the 3rd parties if they want to invest into Switch 2 or not. Will it be possible to port a technical state-of-the-art PS5/Xbox One X (open world) game? Probably not but that's fine.
I have to admit that sometimes I also fall a bit into the AAA-3rd party trap when it comes to the success of a Nintendo console. While they are nice to have, the grand majority of people buy a Nintendo console for their IP's. Although it's known how strong they are, sometimes I forget HOW strong they really are. In addition, all the indies and classic games fit Switch perfectly as they are nice to play on the go.
The question I can't really answer is just how much and what kind of 3rd party support a Nintendo console needs? Clearly, as strong as the 1st party lineup is, ONLY with 1st party titles, a Nintendo console wouldn't sell well. So why is the Switch so successful (besides 1st party titles)? The AA- and AAA-ports are nice but I honestly don't think they drive console sales much. So, it must be the indie titles, but which indies? There are tons of them, much shovelware and cheap shit. I guess it must be mostly those games inspired by 8- and 16-bit games (RPG's, Action-Adventures, Jump n' Runs, Hack n' Slays and generally Roguelikes and Roguelites).
I think the issue is that you’re trying to look at it on an individual game/genre basis when you should be looking at the overall package.
Switch has a pretty well rounded variety of 3rd party games ranging from indies, Japanese titles, kid/family friendly titles, retro games, previous generation ports/remasters, free-to-play games and the occasional AAA showcase title which together span just about every genre.
It’s a combination of quality, quantity & variety.
When the herd loses its way, the shepard must kill the bull that leads them astray.