I've been informed that a popular PlayStation emulator, called DuckStation, became proprietary software (was GPLv3, now PolyForm Strict 1.0.0 which restricts non-commercial usage and modification).
DuckStation was Free Software. I've decided to archive DuckStation from before the license change. Please see:
https://codeberg.org/vimuser/duckstation
If you were using it, please ask the devs to change it back to GPL.
Hardware preservation matters, as is preserving that preservation in a free-as-in-freedom way.