I don't think I wrote that quote, but IME writing to one's MP just produces a pre-prepared standard response letter.
The best thing is creating awareness, and like it or not pilot forums are effective in that. Look at the bizjet community - probably 99% of them are still totally clue-less about this stuff. That's because they fly instead of chatter
Re the earlier stuff, I don't see there has been any organised top level anti N-reg move in the principal "GA" countries i.e. UK Germany and France. Not even recently.
As I've said, the CAAs get most of the money off the N-reg community anyway, via maintenance facilities, and the Govt gets the tax via avgas (whose purchases by the IFR community are substantial). Route charges are collected off the lot. The only bits they don't get are license renewals and AME fees which amount to a miniscule % of the "flying taxes" one pays. The average IFR pilot probably pays more money to Jeppesen
Hey - there's an idea. Tax Jepp
N-reg GA seems to have been happily tolerated by the regulators in these countries. They had ample opportunities, and means, of clobbering it. (I won't list some obvious ones). But they very deliberately didn't do that. They merely prevented foreign regs being operated for money and this kept flight training and most AOC ops on the local regs, thus protecting the bulk of the income stream.
I think the EASA FCL anti-N-reg stuff is a
private project run by a few individuals in Cologne. Looking at the "legal" crap they have drafted and forced through the transport committee, they are not even particularly clever.