As a budding young computer geek and mildly OCD person I always hated the non-square pixels. As far as I recall, square pixels just didn't exist at the time. Maybe at Xerox PARC or somewhere.

They never quite looked right, and making pixel graphics was a bit of a hassle since your perfect design on graph paper didn't look the same on screen, etc, etc, etc. I mean it wasn't life-threatening, just a tiny source of never-ending annoyances.

My Macintosh 512e (one of the early "toaster Macs") had square pixels and it was so great to finally have them.