70's porn was so amazing, the stories turned you on before the sex itself and really in contrast; the acting was pretty decent, soap opera acting but acting nonetheless, if you can stomach bushes then 70's porn is the porn for you.
Up to the mid eighties it was good, then come late 80's hair styles and sets were awful but the stories stayed good.
I don't have an exact opinion on 90's hardcore, but the softcore stuff was pretty good.
Late 90's and on there is no story, if there's a premise it's told and horribly acted in about 5 minutes and then usually forgotten half way through with a lot of forth wall breaking and for some reason comments from the guy filming. RIP Porn.