This macro no longer works for me in Catalina. It executes, but dates on folders remain unchanged while dates on non-folder items selected in Finder change to the 1st of the current month and year. Does it work for anyone else?
Sorry, since I'm running Mojave, I can't really help with Catalina, other than to suggest that it might be some type of permissions issue. You might try running the script (modified to use a manual date) in Script Editor, and see if that works.