If your looking strictly at "wrestling" from 1990 to 1999, im not sure i'd say the wrestling was better.
BUT
The wwe put more emphasis on having better matches, than they do today. Certainly over time, the wwe introduces more moves and whatnot, but comparing the eras the 90's had better wrestling respectably. Today its really more about the entertainment factor. Back when Hogan left, they tried to go back to the basics with Bret Hart and HBK. It didnt produce booming business, but the wrestling was great in certain matchups. They did their only 5 stars matches in the mid 90's. When the attitude era rolled around i'd say the wrestling was decent, similar to it is today, BUT the early mid 90's for that era was really good.
Also throughout the 90's the tag and IC belts meant something. More so, earlier in the 90s, but the value stayed throughout the decade. I think thats another important factor, that really adds to the match while your watching. Perhaps not so much on a old tape, BUT if you were watching during that era, it meant more. Both division were more competitive.
So to answer your question, i think the attitude eras wrestling is similar to todays, BUT early 90's was better for that time.