For much of the 90s it was mostly a hub + rim + spokes kinda thing. "wheelsets" grew in popularity, and are probably still growing in number.

Oldschool HEDs are the first that pop into my head. Various other plastic wheels, of course. Spinergy, Aerospoke, Specialized,

On the mountainbike side, on mombat.org, the first mention of a Mavic Wheelset is in 1997, the Crossland and Crossmax wheels, specifically.