I think Supernatural had a mixed effect. I never liked it but I got into him around that time, I did know other people my age who liked his classic stuff and didn't like Smooth/Supernatural. He probably got more exposure because he had a new hit album, and got more play on classic rock and oldies stations.
The re-issues of those early albums came out the year before Supernatural, and were presumably part of the same push for a Santana comeback.
I did also know people who were turned off from listening to him because their first exposure was a bunch of pop-duets with corny-ass white people.