I was going to mention Cantrell and Dimebag for the 90’s, but felt I was sticking too close to my preferences.
I can definitely thank Cantrell for getting me into heavier music and these days it’s like you can throw a rock and hit someone my age who started playing because of him.
Dimebag definitely gets credit for keeping technical guitar playing/solos in “popular” music throughout the 90’s. Of course you still had EVH/Vai/Satch/Petrucci putting out stuff in the 90’s, but it was still a good decade before Petrucci cemented himself as one of the big guys and Vai/Satch weren’t selling millions of albums in that period.
Head and Munky, too. While they were the antithesis to the above, those dudes got so many kids to pick up a guitar, often times being a 7-string right out of the gate in a time 7’s were still being scoffed at. The kids they got to pick up a guitar didn’t give a shit about anything that came before them but still had great fervor for picking up a guitar.