They’re only going to take him off the primary ballot.
It would have no effect.
States are free to appoint electors as they choose, but theyre not free to set requirements to be president, those are listed in the constitution. I dont see this standing Supreme Court scrutiny because it would open the door to all kinds of crazy schemes in the future. Whats to prevent a state from refusing to allow someone on a ballot if they dont declare their support for gay rights, etc.?