You would be guessing wrong! Even if time travel was achievable, you won't find any N90S, F4 or F5 in 1985 or even 86 or 87! They didn't existed at that time! The F4 was introduced in 88, the N90S (F90X) in 94 and the F5 in 96.I would guess that if u time traveled to the mid 80s youd find more pros using the n90s than the f4 or f5.
In the mid 80s, professional photographers were using mainly F3 and/or FM2. I know I studied photography with one in 85 and he was using a F3, while I was using my father's Petri FT!