In 1.2, if you hide several fields in two layers and then join them, the joined table has all the fields turned on. ArcMap 10.2.2 performs as expected, with only the visible fields visible in the joined table.
Can the ArcMap behavior please be migrated to ArcGIS Pro?
EDIT: To clarify... If you turn off fields in layer A and layer B, and then join layer B to layer A, layer A will retain the hidden fields but all fields in layer B will be visible in the joined table. Then, when you remove the join, all the fields in layer A become visible again. Layer B's table by itself always maintains the field visibility settings. ArcMap retains field visibility settings after join removal, too.
So, two things to fix:
1) Retain field visibility settings after join
2) Retain field visibility settings after join removal