It's still pretty edgy. It's just not only edgy. Most of it serves a purpose too, though sometimes that purpose is just to create a certain tone. I haven't bothered to go through most of Ennis's work, but I liked the boys a lot and parts of other things I've seen posted. I'll probably give them a more thorough read through someday.
I feel like the overuse of edgy has somewhat muddled the different kinds of edgy. There's edgy that's essentially just being poser. Everyone can tell it's trying to be transgressive or shock, but it mostly just comes across as silly or too try hard to actually evoke a serious response. But edgy still has a more serious bent to it and that's from edge that actually has that edge. Actual transgression beyond thoughtless attempts to shock. That bit that genuinely pricks people in a way beyond simple schlock gore or sex. The Boys has plenty of both, with even the more schlocky kind at least serving as either honest comedy or just to make things look that much grimier.