Switch 2 will be backwards compatible with Switch

There isn't a technical reason to change the cartridge format. I don't see why they wouldn't just use the same carts if backwards compatibility is the goal.

there always is:

- smaller

- energy efficient

- cost saving

and they are all valid reasons, it's a handheld, the form factor will evolve until perfected

they could have made them smaller the first time around, but I have to imagine they intentionally chose not to — we have to remember that they're also optimizing these things for children... so smaller isn't always better for things like swallowing (which is why they add a bitterant to the current cards)

The carts are already plenty small. Yes, they could be smaller, but any smaller (without being downloads only) and they'd be difficult to handle.

For cost, they could likely reduce the pincount for new cartridges, by changing the number of data pins, but that doesn't preclude using the same slot. Reducing cost of cartridges is more effective than reducing the cost of the console. Reducing pin count would probably save more money than shrinking the small amount of plastic case.

For energy efficiency, maybe they can eliminate 3.3v and only keep 1.8v for new carts, maybe redesign the insertion detection pins to detect old and new.

There are now cart dumpers that can copy and store multiple Switch games on an SD card. If the same form factor is used its likely these will still work for original Switch games.

Even at the size they are, I wish they were closer to GBA—cart sized.

I would be unsurprised if the cartridge has the same form factor but has internal differences for Switch2-only games. If they want to try to lock Switch2 cartridges down more, there's plenty of ways to do that while maintaining a similar enough form factor for Switch1 compatibility.

Because they can get more money by selling the same game twice. But they can still claim backwards compatibility with download-only games.

You wouldn't vacuum a cartridge.

I suspect the cartridge will be similar but have a notch on it that prevents it being inserted into a Switch console.

This is how Game Boy Color, DSi and 3DS systems handled being able to accept games from older models worked.