The output isn't the whole story, though. For instance, with Spy vs. Spy the graphics were made on one system and then ported to another system with no regard of the aspect ratio of the port. So it can definitely be that the video output of the system should be 4:3, but the game itself should actually be viewed in a different ratio specific to that title.
Also, this article doesn't go into it, but there is a problem taking screenshots and video recordings of games from emulators because they don't usually embed the aspect ratio into the media file. So when they files are viewed on the Web they look wrong. I did some tests with this recently -- YouTube supports AR metadata. More tests here: https://bsky.app/profile/pekkavaa.bsky.social/post/3lbyzru2e...
Also, this article doesn't go into it, but there is a problem taking screenshots and video recordings of games from emulators because they don't usually embed the aspect ratio into the media file. So when they files are viewed on the Web they look wrong. I did some tests with this recently -- YouTube supports AR metadata. More tests here: https://bsky.app/profile/pekkavaa.bsky.social/post/3lbyzru2e...