Will it ever happen? Somehow I think not? I think there are too many problems as well as legal problems enacting these laws as they stand and some sort of BASA is the only practical way forward.
You keep saying that, but so many things have had exactly the same issues and have still gone through involving factors of 10 more EU citizens being restricted if not out rightly stopped from doing there jobs which they have done for most of their lifes. Including professional pilots in the EU who used to be able to fly with a night restriction on a CPL but now can't. So cannot now earn a living from teaching CPL level because they don't hold one.
The lobbying that is going on from the other side to get it through is astronomical. And that's from industry and the civil servant side of things.
They don't want European citizens flying in Europe with a European license what ever flavour of nationality of the aircraft.
It would be a very silly employer who would take on anyone to fly a N reg in Europe without dual licensing. Also I suspect apart from a minority of die hards, I ain't doing it on a point of principle I suspect most are jumping through the hoops.
What ever you say it isn't that expensive to get converted, the exams aren't that hard.