Wrong.
I've used every emulator including the switch emu, and not only do you randomly lose saves, you can lose duplicates.
I've used emulators on laptops, desktops, phones, etc.
And I have even transferred saves between them and see files being corrupted.
I have- right now, saves over 20+ years old (tales of fantasia in japanese).
I just lost 10 hours of gameplay from Seiken Densetsu 2 on Emu Deck last month.