Nintendo did some bad choices in the past that affected them in the long term. Many of those, are no longer part of Nintendo's policies, however there are scars nowadays. However, in my opinion, it is true that Nintendo has specific creative and audience advantages (including a pretty strong brand recognition) that other companies don't have, which are really profitable and kinda work only for them. That and the fact that many tried to succeed in a field that only Nintendo knows and dominate and the rest fail clearly generates resent in some other studios, since many want a piece of cake and they would prefer Nintendo to stand aside.

nintendo... generally works well by themselves, meaning they don't have as much incentive as MS or sony to woo 3rd party devs.

That being said, if anyone wants to be in japan in any capacity for the next 5 years, they'll have to jump as the ps5's sales there is a foregone conclusion of massive shrinkage. ps4 only sold as well as it did becasue there was no competitor for the first half of its life.

How so? They’re using their resources for better ROIs elsewhere.

If you look at family titles, third parties seem to have no problem supporting the Switch. LEGO games or Minecraft or Starlink or Crash Bandicoot or Spyro or Sonic or whatever and third parties come running. 3rd parties do buy into the "Nintendo is kiddie" stigma I think more than anything else.

It's stuff like GTA and COD and Madden that they are more skeptical on from the looks of things, but stuff like Witcher 3 and Mortal Kombat are selling pretty well on the Switch, but they need to continue to grow that.

I cant help but wonder if its partially bexause of how secretive 10do is. I get the impressionsonysoft develop their hardware w 3rd party feedback so they can have AAA 3rd party games at launche. When 10do unveiled the switch it seemed like 3rd parties were mostly taken by surprise. That means by the time they can make a quality AAA game the lifecycle is half over. As far as the online games like COD, no one (myself included) is going to be drawn to a system w no party chat to play games online.

I've heard that during the process they did talk to some companies: apparently Capcom talks ended up with an increase in power somewhere in the formula. What PS4 and Xbox do can only be pondered about.

Some genuinely have I'm sure, but a lot of the blame is on Nintendo. I think you could argue that Nintendo resents more 3rd-party publishers than they get resented themselves. Final Fantasy VII was a big fallout moment for Square and Nintendo. Square had ambition with Final Fantasy VII. That ambition would've required about 30 64DD disks instead of 3 CD-ROMs. Nintendo basically told Square not to come back after that. While Square still supported Nintendo platforms, it was to a much lesser extent than PlayStation.
EA was going to have an "unprecedented partnership" with Nintendo, but then they all but abandoned Wii U after 2013. You could say similar things about Activision. I don't think EA and Activision resent Nintendo in a traditional sense. I think they're just salty that it's far harder to run their games on Nintendo consoles and sell their microtransactions.
Nintendo tends to keep third-party publishers more in the dark than Sony or Microsoft. That can cause some friction. And let's not even get started on Nintendo's very greedy licensing policies during the NES days.