I'm new to Blender and 2.81 is way too different.
I was using the press & hold middle button normally, tried to create a new plane with PBR materials (previously prepared with Youtube tutorials).
Then I typed x, y & z many times to cycle lock/unlock view. No do.
Tried unchecking the transform options "origins" & "locations", nothing.
Tried loading the factory settings, still can't move around with the middle mouse button. Auto perspective unchecked as well.
Just noticed the screen zooms in to the object when pressing Shift + C