Following this....because I have yet to find any scroll bars in Pro. I think they assume you have a multi-directional mouse that will let you move with scroll wheel. I use "C" a lot and "palm" may way around.
I don't see any Enhancement Requests within the internals nor an ArcGIS Idea for scroll bars in Map View. My suggestion is to create an ArcGIS Idea for this item so it gets visibility with the ArcGIS Pro Developers.
Mariyana: Have you tried using the "Heading" compass? I just discovered it. Under Options--> Navigations-->On Screen Navigator-->Pull down to either Heading or Full Control. Both create a compass rose thing in your map window. You can press on different sides and it will scroll. (It also will change your north heading if you're not careful.) But you can press on the ring and it will scroll in that direction. Maybe that is the thing that is supposed to replace the scroll bars.
You can use the PgUp, PgDn, Home and End keys to move around the map, although those don't allow you to directly pan diagonally. You can also hold down Q and move the cursor in the direction you want to pan (behaves like C but doesn't change the cursor to the hand/palm).
Andrew - first, a caveat - I do not work on the ArcGIS Pro Development Team so cannot speak for why/why not of developed vs. undeveloped functionality. In the current release of ArcGIS Pro, 3.0.3, I do not see scroll bars on the Map or Layout view but do have tools to navigate like one did in ArcMap through arrow keys and the Navigator. I did see some related ArcGIS Pro Ideas about scroll bars but not likely the specific funtionality you're requesting. My suggestion is to create an ArcGIS Idea so it gets visibility from the ArcGIS Pro Dev Team.