I am lead to believe this is one of EASA's 'Die in the Ditch' points. To pass a law in their area of competence which explicitly allows individual states to ignore the law is against a fundamental principle that European Law must be applied to all of Europe.
I think that's 100% correct, but EASA doesn't run the universe. They just run a load of committees, whose proposals are published, go for a comment phase, and then go to the EC for lawmaking.
The known universe is run by the European Commission. That is a bunch of politicians, who work in a different way to the EASA types. This is why when say Cessna wishes to protect the N-reg scene in Europe (which is probably pretty important to their high value jet sales) they are not going to type up a Response # 13556 to some EASA proposal. They will spend 5 figures on a lobby firm operating in Brussels. That's where it all happens (or not) in the end.
It is this lobbying that has successfully brought the EASA proposals to the surface of the political whitewater (or foaming cesspit
) and resulted in the recent open rebuke to EASA which - if the press reports mean anything - will probably result in all hot potatoes going on the back burner and should result in my "status quo" option above.