That's not a good idea because the only way for that to work is to downgrade to an older version that doesn't have the Taproot code (so it considers it non-standard) so that it stops relaying them. But it will stop relaying ALL Taproot transaction instead of only the spam ones which is not what we want.

The other problem is that your node would also be incapable of verifying Taproot transactions in blocks which means it will no longer be a full node and if everyone does that, the security of the chain is threatened.