At first, the handmade emulators were just as buggy and crashed all the time. That’s just normal during development. With AI tools, however, you now have the advantage of being able to theoretically create a comprehensive testing environment where, eventually, an LLM will play the games on its own and fix any bugs it finds, so that the user ends up with a nearly perfect emulator.

The Switch 2 is a completely different story than other consoles. To create an emulator for it, you'd have to be able to reverse-engineer the Switch 2, and that won't be possible until there's a jailbreak.