It might not be the norm, but it is a perfectly acceptable build. One of the things 5e has done really well is allow non-optimized counter-intuitive builds still to be viable and fun.
I think one reason it still feels like playing against type to many people is because it's not just about D&D. In D&D style heroic fantasy in general (LotR, of course, but also recent stuff for the newer generations like Dragon Age) dwarves are often not wizards, or even capable of being such. It's a longstanding tradition in many popular franchises.
No, dwarves have been arcane casters for a long time now in D&D and in most video games with them in it, Dragon Age is about the only major rpg I know of where dwarves are barred from using arcane magic.
Oh, it is still against type. There are some people who play dwarf wizards, or who have just forgotten about this aspect of the dwarf culture, but it's an option many DM's will actually disallow.