Couldn't agree more with mm-flynn.
As a general comment on bose-x's posts, unfortunately warnings about impending doom (in aviation) are two a penny. So nobody is entitled to claim credit for drawing attention to some hypothetical measure. In this game, there is always somebody trying to get you - pop along to the next NATS or Eurocontrol presentation and listen to the garbage about GPS not being acceptable for navigation. That boat left the port years ago but they still bang on about it. If they could, some of them would ban all GA (i.e. pilots with gold plated JAA IRs flying Cirrus SR22s) from Eurocontrol airspace. Of course they cannot (ICAO).
This EASA proposal is just another proposal. OK, it is nearer to reality than previous ones, but I am sure you all remember the bizzare UK DfT one, kicking out N-reg after 90 days' parking. That one had everybody's knickers in the twist, with some N-reg owners going back to G-reg purely because they were scared! How daft, when they had nothing to lose by waiting, and taking action only when mandated.
This is a cleverly worked out proposal, which takes advantage of a country's right under ICAO to shaft its own citizens in its own airspace in any way it wishes, and which is going to affect the usual players in the same way as booting out N-reg airframes from Europe would have done. So, expect much mobilisation of lobbying power - just as previously.
We must do our bit in the response to the NPA, of course.
IMHO, the final set of rules will be very different from this proposal - not least because this is very vague.
4 years is an awful long time in politics.
Some things could be harder than having to sit 4 JAA exams. Imagine a hypothetical mandating of Enhanced Mode S for PRNAV airspace. Imagine the massive avionics refit you would need to do to collect all the data in a form suitable for squirting into your GTX330 so it can be radiated on 1090ES. Easily well into 5 digits.
Finally, what we see here is the STICK. There is likely to be a CARROT. Certainly so, if they want to avoid a war from the bigger operators (turboprops and corporate jets). The carrot (e.g. FAA to EASA conversion rights on both certification and FCL) has not yet been published, and won't be for a long time, because in EU politics you have to keep the best meat in the bag, for the biggest dogs.