Perhaps I did not express myself very well. My point is this: by international rules and by US law a pilot of an N reg aircraft must have a valid FAA licence, passed a BFR and hold a current FAA medical applicable to the type of flying he is doing. The imposition of a second layer of licensing which is not required in any other jurisdiction in the world means that as far as EASA land is concerned a pilot may be flying legally even though by any other international standard he may be illegal. This as a matter of principle seems wrong and violates what courts in international terms refer to as the comity of nations.
To make this work officials will it appears have to concentrate on enforcing EASA rules at the expense of the rules of the state of registry of the aircraft.
A person's residency (EU or not) is not some vague and grey thing for 99% of people. All a ramp inspector has to do is get you to sign a declaration. At that point you can either own-up or lie. I don't believe anyone is going to take this risk flight after flight. It's just silly to suggest it. There is a question about the definition of "operator", which I suspect would easily be resolved to capture any bona-fide private or group flying.
I don't think you can make such a sweeping statement without some evidence to back it up. The sort of people who will be caught by these rules are just the sort of people likely to have ambiguity over their residence or where they are established. So, if a pilot is asked to sign a declaration and refuses, the sanction is what? He has an address in New York and one in London! So far this year 60% of his time has been spent in London but his intent is to spend the rest of the year in New York. Where is he resident for these purposes? If last year most of his time was spent in New York is he resident their even though this year he may spend most of his time in London. A person may be resident or established in one state even if he lives most of his time in another, as his intention is always to be considered a resident of the first state. This is a concept known as domicile, which exists in common law jurisdictions but not in continental systems. One can go on and on. But, in the absence of a definition of when someone is deemed to be resident in or out of the EU how is a pilot to know and more importantly how is the official trying to enforce this to know. It will be a very subjective judgment in many cases.