Mike, your statement of "unintended consequences" parallels the thoughts that popped into my mind as well. You KNOW that hundreds, if not thousands, of older birds will fall through the cracks of re-registration. The owners will then play HELL trying to get them reinstated.
Honestly, I take no pleasure in being so pessimistic about the long term future of our hobby...but can anybody here list a few things the FEDS have done in recent years to help us keep our "legacy" airplanes safer and modernized, such as being able to legally use affordable new technologies, parts, and materials? All I have seen is road blocks, both to piloting and owning our aircraft. It's hard not to believe there isn't some hidden long term agenda to eliminate a few hundred thousand pilots from the FAA's data base.
All we can hope to do is keep up the good fight and support organizations that promote GA, even if we don't agree with everything they do. We need all the allies we can get (even if we're envious of their pay raises
)
I don't see our hobby as going away in the short term, but I'm pretty sure my grandkids won't be flying anything that doesn't bear military insignias.
What a bunch of sad sacks we are. 
Read the 172 electric post on Everthing Else. But I agree with Dan. Im going to enjoy flying while I can. Im not making big future plans or serious investments in flying. Just as long as the plane is safe! Casue I know at the end they will be tooked to salvage yard like my old car. Almost puts me in tears talking like this. But its sad realitly.