Comment by arexxbifs

One problem is that we've become so conditioned to seeing some of those iconic games with square pixels (because of emulators and screenshots) that the original aspect ratios look unfamiliar.

This is true also for most Amiga NTSC and DOS VGA games (both 320x200 on 4:3), such as Monkey Island. Here's an interview with Amiga artist Jim Sachs where he laments the lack of 4:3 aspect ratio when his works are displayed on modern machines: https://www.amigalove.com/viewtopic.php?t=1618

Some artists may of course have adjusted their screens in order to get square pixels, but I think the safe assumption is that they wanted to fill the typical default viewing area with graphics, since most users didn't (or, in the case of many cheap old TV sets, couldn't) adjust their screens.