When moving Sockets around in Orthographic View with Snap to Grid enabled, Sockets snap to the Position Grid Snap value when moved along the Grid. In Perspective View this is not the case and moving any Sockets acts as if Snap to Grid is disabled even if it is enabled.
This issue was found and tested in 4.18.3 (CL- 3832480). This bug can also be reproed in 4.19.2 (CL-4033788), 4.20 Preview 4 (CL-4154964), and Main 4.21 (CL-4169600)
Results: Sockets don't snap to the grid in Perspective View but they snap in Orthographic View.
Expected: Sockets snap to grid in Perspective View
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-61319 in the post.