I guess I was thinking of hard and heavy rock as in 80's metal. I think it's fair to say that the majority of bands used Charvel's/Jackson's, including Steve Vai in the early 80's---and others throughout the 80's.
Also, the higher end and custom guitars from Jackson/Charvel used original Floyd Rose Trems, Not the JT stuff. Just as Ibanez' lower end uses the Lo TRS, Jackson uses alternate bridges on the lower end stuff.
I would agree that Jackson is not doing so hot these days, most people don't want the pointy headstock guitars anymore.
Ibanez' headstock is somewhere inbetween I think. When you look at it you don't think, "that's an 80's guitar"
Perhaps Ibanez is the current heavy rock guitar leader. I am after all stuck in the 80's. Music in the 90's was horrible for the guitar with a few exceptions---well, imho anyway.