Switch 2 will be backwards compatible with Switch

It would really be surprising if it wasn't backwards compatible. The Switch breaking backwards compatibility was exceptional, apart from that every Nintendo console since the Wii on the stationary side and the GameBoy Color on the handheld side had at least one generation of backwards compatibility.

That's an oddly cherry-picked version of a pattern. There was no compatibility between the NES, SNES, N64, or GameCube. Wii and Wii U each supported their predecessor's games, but the Switch did not. Those 2 out of 7 were outliers

You are forgetting the handheld line

Gameboy Color supported OG Gameboy games

GBA supported GBC games

DS supported GBA and(?) GBC games - Could be wrong about that

3DS supported DS games.

The important part is that backwards compatibility became a focus after the Gamecube and it has been ever since. Like, this is just a fact. The Wii supported Gamecube games and controllers. Even the WiiU had the internal capability to run GC games, it just lacked the disc drive for it, and it ran Wii games just fine. The same goes for every single of their portable consoles (GB games work on the GBC, GB and GBC games work on the GBA, GBA games work on the Nintendo DS, etc).

DS did not support GBC games.

CPU and GPU architectures used to wildly change from one generation to the next. Backwards compatibility wasn't always practical or feasible.

Now we've arrived at a fairly locked in set of architectures.

"Every console since the wii" and "except the switch" is two consoles. The other 4/6 were not backwards compatible.

The DS and 3DS were.

The GBA (original and SP) also supported OG Gameboy games, but the Gameboy Micro only supported GBA games

The 3DS also had games from other consoles for sale in the eShop, but they were emulated (GB, GBC, Game Gear, NES, SNES). If you bought a 3DS before the price drop, you could also play some GBA games. These are also running natively, not emulation https://en-americas-support.nintendo.com/app/answers/detail/...

Game Boy Micro can still enter GBC mode, it just can't read any cartridges. It's missing the switch which is normally triggered by the cartridge shape, and also missing the voltage conversion circuitry.

A lot of people call those handhelds to distinguish between them and traditional consoles which attach to a TV.

The SNES architecture looks pretty similar to the NES architecture in a lot of ways. It might have been possible to make it work, if it was a design goal. The PPUs are similar, the CPU has a compatability mode for the NES CPU, the controller bus is the same with a different connector.

Sega does what Nintendon't, and their 16-bit system was backwards compatible with (one of their) 8-bit systems, if you got the adapter that adapts the slot and includes a boot rom.

Apple also did it; the 16-bit Apple IIgs used more or less the same CPU as the SNES, and used the CPU compat mode to run regular Apple II software.

Sega

> The important part is that backwards compatibility became a focus after the Gamecube and it has been ever since. Like, this is just a fact.

It's a fact until 7 years ago, when the Switch was released without the ability to accept Wii U discs or connect to Wii controllers. Two upgrades with BC did not establish a pattern.