throw it away and get a prusa mini ;-)

I pretty much never do anything to my printers after printing.
I clear any filament off the printbed, but that's it.
If using pla and not going to be printing again for a few days - good idea to unload. But other than that - most machines are fine as they are.

That said, ender 3's have a LOT more problems than most other printers. But filament left in overnight, shouldn't be one of them :-)