Maybe it was even a 25 pin delta serial? or an external scsi port? Sounds damn peculiar indeed.

This is a great explanation!

But I do have to say, you darn kids with your fancy newfangled PS/2 input… in my days we had proper serial or DIN ports!

It was amazing for years and then they ran out of money. When it completely crashed and went full ad insanity and crashed again, someone else took over with the intent of making it great again. That may be a poor choice of words or it may not.