Hi Sven -- the sad thing is that I can imagine younger engineers saying to themselves "Bell Bottom Trousers -- what are they?"
I recall having ones that wrere 22" around the bottom -- looking back that really was a pretty ridiculous style (not as silly as the platform shoes, of course) -- now I'm wondering what my father thought about it all :-)
I never throw anything away, I still have a box of leaded resistors, capacitors and old 7400 series IC's from my college lab so why notkeep the old pants also. I don't think they will fit me anymore and I'm sure that if I tried to put them on my wife would send me to the Oregon State Hospital for a long long long vacation.
There are many proprietary buses at that time. There are still some today but most test equipment uses GPIB, USB, or Ethernet with some also using RS-232/422/485 thought those are more for industrial use now. UAB has replaced RS-232 in many small pieces of test equipment.