They might realine in 10-20 years time. BUt they can't do it now until all the previous people that went N reg in europe have been made to convert over so they haven't recieved any benefit compared to those that have stuck with local reg.
It is a loophole you have to use as a none US person to even be able to own your plane. If it was only US passport holders or even green card holders that had N reg in Europe nobody would give a toss.
But you pay a company to hold your plane in trust which as a none US citizen your not allowed to own, with a N reg.
Looks like a loophole to me.