I think a lot of had to initially do with Periphery using the Axe. (and metal is fun , being able to get a cranked 1/2 stack sound without blowing your ears out is priceless)
They are pretty big with the younger crowd so the next wave of metal wannabes have embraced the Axe as
a good working solution. Plus Misha used to be very accessible and visible on a few forums and would constantly post great sounding clips using the Axe when they were doing their initial writing.
I'm sure those clips sold a lot of Axe units early on.
When the bands you're into are suing a specific piece of gear , people tend to latch on to it. (look at all the VH clone amps that are still out there and popular)
I myself like a lot of metal ( and dislike just s much) but I am more into shred/fusion , the Greg Howe/Kotzen joint offerings are my favorite style of music.
I'd love to hear some more clips of that style (I am just getting around to writing a bunch of stuff in this vein, if I can get my drum programming up to speed I will post them )
that and most types of Shred, the Satch,Vinnie Moore.Yngie, Vai stuff and we do occasionally see clips of the shred genre posted here, but those are usually pretty high gain as well.