By jove, I think you are correct, Doc. Initially, the change icon dialog wouldn't open for any desktop icons but after the reinstall, it is opening normally for non-MS365 icons. Maybe SD can work their magic & get past the block, cause the 365 icons suck and the document icons are almost blinding in Dark Mode and list view which is of course what I deal with all day.
(One can hope, right?)
Hope all is well with you, Sir.