Numpad 7 gives you top view, ctrl-np7 gives you bottom.
Is there a way to get to those views but with the Y-axis reversed?
In a single key, no. You can use numpad 4 and 6 to roll the view around, though it’ll always reset after a view switch.
Someone on FB reminded me of the existence of STORED VIEW, so huzzah.
I enabled it in Texture Paint view, and Blender vanished/crashed. Noice!
Ten minutes later, crashed again. I don’t think Blender/Texture Paint like “Stored Views” very much.