I agree. I can remember that Nintendo's President Shuntaro Furukawa said not too long ago that (on a Q&A of a financial report I guess) that they are currently not interested in buying 3rd party studios because it would be very difficult to infuse into them the Nintendo identity (which stands for a special Nintendo quality, creativity and innovation). Although, I personally think there are lots of talented 3rd party studios around that would complement Nintendo's lineup with more diversity and the respective 3rd party studio's own quality identity, even if we would agree with this statement it still begs the question why then not build-up new in-house teams? They have plenty of money to pay the best talents in the industry and to pay for additional space needed, hell, they could even invent their own talent pool, kind of a Nintendo university to instruct young talented people from the ground-up, surely many of them would want to work for Nintendo afterwards.
It is by far the biggest critic I have on Nintendo: Why not use some of your money to build new development teams? It would ultimately result in having much less (quality) software droughts (and would quell most of such critical threads like this one).
Nintendo has been hiring new graduates to be part of their development teams so they're kinda doing what you're saying in the last sentence of your first paragraph.
As far as developing teams, it would take months (if not years) before they could even start up, let alone develop a game. Nintendo is already managing multiple teams within EPD and teams such as iQue, Retro Studios, NDCube, and Monolith Soft, let alone working with developers such as Intelligent Systems, HAL, Game Freak, Good Feel, Grezzo, Next Level Games, Camelot, Genius Sonority, and Sora, Ltd. There are other teams and studios Nintendo has or are working with that we don't even mention much because they either are working on smaller titles or are mostly support teams.
I don't know what's the mindset of Nintendo in regards on what they spend and how much they spend on projects. But they seem to have a grasp on what they need or not need at this time. If they feel that a new in-house team will not be financially worth it, then that's their stance.
Edit: Not to mention Nintendo is continuously working with third party developers to develop new games. Astral Chain from Platinum Games is an example, as well as the recently announced Hyrule Warriors: Age of Calamity from Koei Tecmo. Koei Tecmo even developed Fire Emblem Three Houses alongside some of Intelligent Systems' team members.Last edited by Kai_Mao - on 15 September 2020