If there were sidechains, there can't be any check on their validity other than the soundness of their scripts. They need to be protected by consensus and the power of Bitcoin. It is up to nobody to preemptively judge the validity of the ApePunk9000YeMuskInu-token.
If we ever came to discuss why a miner disallows the ApePunk9000YeMuskInu-token but the DeSantis24FuckWoke-token is granted, Bitcoin has died a long time ago.