If we extend to all rock/metal adjacent players that don’t use a Jazz III, the list is gonna get long pretty quickly. IIRC Steve Vai, Joe Satriani and Kiko Loureiro all use Ibanez picks. Teemu Mäntysaari uses custom Wintersun Dunlop Ultex Sharps in 1.0mm. John Petrucci has transitioned away from Jazz III to the Flow line and his custom Trinity, which is basically a triangular Flow. His promo partner for the Flow line, Andy James, uses a custom Jumbo 2.0mm. Also, given the shape, Jason Richardson’s signature Jazz III is a Jazz III in size only: the profile of the pick is completely different, it’s basically a smaller Jeff Loomis signature pick. Even John Petrucci’s first signature pick was a Jazz III in name only, the shape was quite different.
Just going to the Artist picks page of Dunlop can give you some pretty interesting results.
For someone really classic, Friedman seems to use a not very fancy classic Dunlop celluloid, which seems to have the infamous Fender 351 shape.
Also, might as well plug in Troy’s video on choosing picks.