Surely you cannot copyright "functionality" even in the US, is this not a bogus DMCA? Is there anything that average folk can do against these notices when they're sent to companies like GitHub?
They can file a counter-notice, commit to accepting service of process if the other party wants to sue, and wait 10-14 days. There's a guide at https://docs.github.com/en/site-policy/content-removal-polic... and there are plenty of example counter-notices in the https://github.com/github/dmca repo.
Not a lawyer, but my underatanding is "No." That is why you can find so many different "opoly" games that look very similar to Monopoly but do not use any of the same branded words or cornerspace graphics.