USB Flash Drive Corrupted While Copying File (can't format)
Solution 1:
It's permanently broken.
Flash drive's controller is now in read-only mode. Opening files probably doesn't work because it's trying to bump the modification date, which requires writing to flash. Recovery tools work because they use raw disk access and don't write anything.
This kind of failure is very common. It's caused by flash memory failure. Controller manufacturer's tools could maybe reset it into normal mode, but the flash has failed anyway, so it's a matter of time until controller realizes that it's not reliable and switches into read-only mode again.