I can confirm the same behavior: open "Profiles" page, a lot of paths listed under "Folder & Workspaces" (many of them temporary ones I deleted long ago), the small x on the right is displayed but doesn't work (grayed out).

However, I might have found a way to clear them all: goto "run command" and find "Developer: Reset Workspace Profiles Associations". That is very brute force, so hopefully the x will be working soon ...

My VSCode version is 1.95.3