Title: installing battle net is a bit of chore, but other than that was very impressed with how smoothly this runs on steam deck. Combined with Steam Dock and instant console mode. Highly recommend.
In terms of using steam deck? Don’t think they have said anything one way or the other. Can’t imagine they would care, steam deck is really just a PC dressed up to look like a console so essentially the same as playing on any other computer. Especially for Diablo 4, they want your money…..they want you browsing the shop and buying things, I don’t think they could care less if that was on a calculator so long as your credit card works lol