Issues with Previews

This issue keeps coming up through various versions. I'm currently using LR Classic 130.1, Mac OS 14.1.1

Previews keep not showing up. Library mode, Develop mode. Both have issues, but they vary. In Library mode I can have all or some previews missing and nothing seems to get the missing previews to show. In Dev mode, a few might show and sometimes clicking on an image with a missing preview will cause the preview to suddenly show. Usually when one preview does show up after clicking, one of the other previews disappears.

Restarting LR makes it seems like things are solved, but the problem returns quickly. Shutting down, restarting, reinstalling does not help. Rebuilding previews does nothing; the progress bar just sits never makes any progress. I try to backup the catalog but it always hangs up on Optimizing previews and never finishes. This seems to happen with all file types. Raw (CR2, CR3), JPG, PSD...