1. Never had any issues.
2. Stop acting on your "I grew up with iphone, iphone has one button, I click it every 15 seconds - then Im at home screen, what a relief" skills and actually exit the emulator using the "exit emulator" function, instead of quiting out of everything and anything using the home button.
3. That said, save states should be saved to sdcard, as you are saving them - if I'm not mistaken - so point 2 might not apply. Still try it, and lets see if it helped..
If not - next likely issues are: write to sdcard has issue on a certain firmware/hikate combo (unlikely), or SDCard is corrupted (even more unlikely, especially since you could load saves). More likely would be you accidentally having deleted, or renamed the rom, which now results in a PEBCAK issue.
Seriously stop using the home button like an overenthused iPhone user, though. Prevents many problems (basically all apps you load via homebrew menu, dont tend to stay in memory - so the next time you open them, they'll be restarted. Also the Switch os isn't designed as a DAU OS - where every step and state is saved as soon as it is done - it still follows concepts like "do you want to save to sdcard?" and "actually leaving apps has consequences".
"Cool, but I pressed home button, and now I'm home, so what do I do now?"
"Call a friend?"
