It’s called Kodi. It’s a media centre that organizes and displays a library of your own, locally stored (on a NAS or external hard drive) video files.

It can be extended with add-ons for example for watching YouTube, but of course there are also some piracy add-ons, which Kodi itself doesn’t condone, but can’t do anything against

-emulation station is just the frontend and doesn’t do any emulating itself. Did you mean emu deck?

-that’s why I always preferred retro deck, which installs as a flat pack over the discover app (basically a form of an “app store”) and isn’t impacted by any steam deck updates

they do just that if you have location history turned on though