That was def when touring cars what at it's best, all the top manufacturers ran cars, although I've got back into recently and is def getting better again, but no match for back in the day! The A4 ruled, especially in the wet with it's 4wd, no one could touch em. I loved the Volvo estates which were run at the same time too.
As for skylines they simply dominated where they were run. Mainly in japanese and world touring cars I believed, to a point where no one race against them anymore so they spawned their own chamionship, think they were run in australian touring cars too, where again they ruled, even against the rs500s.