is he a straight maj-min pent guy, model or mixed
Are you one of the 1,000,000,000 people who have watched or listened to Sweet Child O'Mine on youtube? Middle section of the solo has a fast E harmonic minor run that he wrote when was 20-21. He's certainly no Yngwie and whether or I don't know whether he knew the theory behind it or not at the time versus it just sounding good. The ending solo to November Rain also starts with a lick in C harmonic minor.Does he use the harmonic minor scale as well as pentatonic and blues scales?
G'n'R were one of those bands I vaguely knew about at the time (I would have been very early teens when the Use Your Illusion albums came out), ignored whilst I was caught up in the indie thing and raiding my aunt's 60s and 70s classic rock albums then bought the albums cheap on a whim a decade or so later and it struck me pretty much exactly as you described - pretty much just fast, beefed up classic 70s rock. It reminds me a lot of Sticky Fingers era Stones as well in that sense.To me it sounds like a hotter/flashier version of the blues rock approach from the 70's. It's not far removed from Thin Lizzy/Slade/T. Rex stuff, just hotter tone and faster licks.
I’m not sure most realize the word pentatonic actually means something.I don't know what it is about TGP, but the standard bash of anyone who isn't Robben Ford (or whom we don't like just because) seems to be "he's all pentatonic".
Go learn a few of his songs and solos and do the analysis, you'll see he isn't, and you'll be better for the work.