I had 10 .MOV files, loaded from a CF, coming out of a DSLR, on a folder.
Opening that folder with Bridge (cc.2019) and selecting each of these files results in a little "play" key under the preview picture: pressing this key there are some essential playback controls, useful for an effective clip preview.

I copied these files on another disk, then erased from the previous place (moved) and the preview keys are no more there. No preview is possible. And also sometimes this happens with metadata fields, previously perfectly editable, are no more editable. These are 2 different cases, but always for a simple "move" operation.
And of course, I verified if there were locked files, "handles" and so on: restarted Bridge app, restarted pc, no antivirus (except for defender) were active.

This happens very often and I must enter in photoshop to see the actual content of the clip. So Bridge doesn't have a real function in this way.