File sizes.
If your online game is built around massive 50 to 100gb updates, you need a system that has a guaranteed large internal memory that requires very little optimisation because your game is nowhere near completion when it launches. Cloud gaming will help remove this hurdle.
You have a few other factors such as a studio being pushed to get a new game out rather than giving them time to learn a new platform because you need a new game out every year, so you end up outsourcing it at a higher cost and the outsourced product is lower quality due the Switch not being treated as the lead platform from the start.
But more than anything, it is the file sizes.
If the Switch had larger storage to start with and cheaper cart sizes then it would be a different situation but that didn't happen. So going forward it will only get Destiny 2, GTA Online, WOW, COD, Sims 4, Battlefield or Tom Clancy stuff by having a new system with absurdly large storage or for Nintendo to pay for it or the Switch sales grow year on year for a further 2 years.

Doubt it, they'd be voluntarily rennouncing to a big audience. Outer Worlds proves the reality of how hard it is to port games intended to be multiplat to the Switch. Not every studio is CD Projekt Red.

No, corporate entities may be "people" according to some, but it's really the owners who hold opinions. For the most part owners range from people who only care about the margins, and people others who have no reason to be resentful to Nintendo.

Some of the older management at Rockstar North might hold a grudge, but I can't think of who else would.

Why do third parties not put certain properties on Nintendo consoles? Because it's not a good use of resources. Nintendo fans are mostly looking for something other than the formulaic AAA schedule Playstation style games, that's why they have a Switch.

This is the problem: it's not a logical decision, it's an emotional decision. Logic doesn't work in this case

Frankly I'd prefer a GTA collection of the older games instead of a mediocre version of GTA 5.

Give GTA III, Vice City, San Andreas, Liberty City Stories and Vice City stories the "Crash/Spyro treatment": same games at their cores and mechanics, but hugely upgrades graphics.

Make the Switch version the definitive version of these games, much prettier than all lazy ports of them before.

Over 100 million gamers already played GTA V... but how many also played the older games? Many GTA5-fans probably haven't played most of them, there is a huge potential.

I don't know if that's necessarily true at this point, but there have been some strange moves that makes you wonder, why isn't it on Switch alongside the other consoles? Case in point, Tony Hawk Pro Skater 1 and 2 HD remakes and Crash 4: It's About Time.

Don't take it from me, but some have said that Nagoshi from Sega and Harada from Bandai Namco apparently don't care for developing games for Switch. Of course, there new and old games released on Switch from BN and Sega, but games like Yakuza, Sakura Wars, Tekken, Soul Calibur, and the new Tales of Arise have not had Switch ports. There was a hint of a possible port of Soul Calibur VI on Switch, but it remains fruitless.

And Capcom is...weird with Switch. Lots of ports (albeit, strangely priced to some) and collections of old games, but very little new, original games or ports of current-gen games. Mega Man 11 is the most notable new game from Capcom on Switch. Ono, before his departure, even said that fans have to convince Nintendo for more Street Fighter games on Switch back in October 2019 (though he later said he hopes to work on more games for Switch).

I guess it depends from developer to developer.

They don’t resent them, they just know nintendo fans buy mostly nintendo, porting games to the switch is more difficult due to hardware limitations, so there’s no profit to be made, look how bad outer worlds, people say but Witcher runs on switch, yes it’s true but it took a lot of time and effort to get it running, companies cannot develop two versions of a game, that’s why crash 4 will get a port later after the game is finished and the developers Can start working on the switch port.

There is plenty to resent Nintendo for, so I would assume so.

I'd say so. Hard to say where the issue lies (and after the Ubisoft reveals of what made creative stagnation, let alone the ideas that were not let through it could be anywhere) but there is a clog somewhere.

In the end, its thier loss.