Settings > Apps > Special app access > Display over other apps

This advice is partially correct, but enabling the feature requires an additional step. While you can try toggling it on from that menu, you'll see a warning and what appears to be a non-clickable (?) link about learning more.

To fully enable it, go to the app's Permissions screen, tap the three dots in the top-right corner, and enable Access to restricted settings first. Once that's done, you should be able to turn on Display over other apps successfully.

It doesn’t feel like users have a clear path to enabling this feature without that link working in the warning.

I am going to have to give that a listen.

The other day an EDM leaning friend had sent me Zeds Dead - BBC Radio 1 Essential Mix (2013) which was uploaded to that same youtube channel around the same time. I thought it was fairly enjoyable if not a bit too upbeat.

That game you are talking about may be GORILLA.BAS.