Having seen both the Decragard (wood) and fiberglass interiors on the 22, I would say there is likely not much difference in weight, and if there is, I'd probably think the fiberglass interior would be a bit lighter. However I would not expect it to make much difference in the overall weight either way.
There are ways to make boats lighter through "techier" ways of building, but I don't think C-Dory uses any of those in particular (honeycomb panels, sophisticated layup methods, etc.). Does anyone know any different about the new boats?
Given all that, I think the biggest differences will come from outfitting, gear loaded aboard, and trailer choice.
Heavy engine(s), large battery bank, bigger fuel tanks (if you trailer with them full), more accessories.... those will add up. Tandem trailer/steel frame will weigh more. If you travel with a lot of gear, then it has to go into the boat or into the tow rig, and both will have some impact on your overall weight distribution/specs.
When I bought my 22, I had a vehicle that had just about 5,000# clear in the specs for tow rating (the actual tow rating was 7,500#, but that was a pipedream as the rear axle weight and gross combined rate both maxxed out when towing around 5,000# -- so that is something to consider too). So I was in a similar place as you. After reading real-world weights here on the forum, I figured I'd be okay - worst case might have to leave more stuff at home, trailer with tanks empty, etc.
Since I bought my boat, I have weighed it many times (mostly in Oregon and Washington, due to their free public scales). I'm at around 4,600# (including tongue weight) with a good bit of gear in the boat but empty tanks (I don't like towing with full tanks anyway). I have a galvanized steel tandem axle trailer, and a mid-weight main engine plus kicker. I've never weighed in at over 5,000#, even with a reasonable amount of gear and full fuel tanks (was a short hop).
I now have a rig that can tow a bit more, but still tow long distances with empty tanks (fuel especially, since it's right on the transom). I'm still well under 5,000#, even after some gear creep. I run around 350# tongue weight (you can go with less than 10% on a tandem). I have read of a few folks up in the 5,200# range for 22's, but if they had to, I bet they could trim back. I mean, I don't think it's anything inherent in the boat that makes it heavier (unless there is core damage or something).
Will be interesting to see if anyone with a "new" 22 chimes in with an actual, all-up trailering weight.
I agree with Jim that it's always best to trust other owners' (or your own) scale weights over builder specs (this goes for all boats, campers, etc. -- it seems there is a tendency for them to be "optimistic" in their estimates)