The Switch Operating system already has the necessary hooks to profile different performance modes.
The Switch 2 should in theory could just be additions to that scheme...

Hopefully Nintendo does a Microsoft and Sony and takes the current Operating system and builds upon it, rather than throw everything out and start from scratch, because that is what will determine the course of action Nintendo will take.

In saying that, if Nintendo builds upon the current software base, then developers should still be able to access the current Switch profiles to build games for in order to optimize for battery life on newer Switch hardware at the expense of performance.

Backwards compatibility however is not guaranteed, there are some big ISA changes between Maxwell and Ampere and some big changes between A57 and A78, it depends if Nintendo can be bothered to abstract the hardware enough, or if it's even possible.

It's going to be fully backward compatible, but I doubt there'll be any noticeable enhancements for existing games. I'm actually expecting a "all games must work on both systems" approach.

I imagine the Switch 2 or whatever it's called will be backwards compatible, the CEO has mentioned the user profiles and BC a few times since 2020. Will there be any upgrades to existing games, very doubtful.

The same "insider" that claims that the Switch 2 will miss 2024 and launch early 2025 said last week that the new console would be Backwards Compatible, and *may* offer some enhancements:

https://wccftech.com/nintendo-switch-2-backwards-compatability/

Take it with a grain of salt.

It's wccftech. Going to need more than just a grain of salt.

Most Games will be backwards compatible with minor improvements similar to overclocking a gen 1 Switch. Loadtimes will be better as well.

Some games will not be backwards compatible, like LABO. These already do not work with the OLED. Ring Fit Adventure is another possible candidate. Obviously it's unsure if Switch2 will have some kind of motion control (joy-cons)

I do not expect (paid) improvement patches for games, eventhough a small download might be required to sync the Switch1 games to the Switch2.

I know what you mean, but this time they provide the sources of the rumor, which are not only th ebrasilian guy I mentioned but also another leaker (whose credibility is unknown to me) backed the testing of the BC feature at ResetEra, but not the enhancements part.

So, at least this time, it looks like you'll be fine with just a grain of salt.

.

Pokemon Scarlett/Violet about to be in a playable state once it comes out with BC.

Jk aside, I am expecting the next Switch to have the full BC capabilities whilst enhancements for previous games with dynamic resolutions, uncapped framerates, longer loading times will receive improvments..

I also expect to see some of the more recent releases to receive patches that take advantage of the system for further enhancements, mainly first party titles.

Stuff like main Mario games, Zelda BOTW/TOTK, Xenoblade Chronicles games, Fire Emblem, Princess Peach Showtime etc ... Will have these patches available ...

But I haven't determined yet if it's gonna be free or not in some cases. Maybe they'll release upgraded versions of them or new Deluxe versions with new content in them as well. But I'm not sure on any of that.