I mulled again over the problem and I think I need to relativize my response. While it's not possible to reliably identify blocks that come from censoring miners (in order to blacklist them), it neither is a necessity for forking away from the compliant (censoring) chain. It suffices that all nodes which want to leave the compliant chain coordinate and agree to reject a certain block X in that chain (UASF). After that, non-compliant miners can build their non-censoring forking chain on X's parent block. The result would be a compliant Bitcoin and a non-compliant Bitcoin. The latter would probably be prohibited from being listed on regulated exchanges.