Don't kid yourself, there is ZERO collectors value in these.
Been supplanted with the CZ 457 which make the previous lines pretty much obsolete.
I totally disagree, with all due respect.
The 452 is the better designed rifle for accuracy, and not surprisingly it's the more expensive of the two to manufacture.
The improvements that you mentioned -- push-to-fire safety and the side bolt release -- are both ergonomic conveniences but they don't improve accuracy, whereas the two big cost-cutting changes they made can negatively affect accuracy, at least in theory.
(1) abandoning the threaded barrel attachment for a dual set-pin barrel attachment.
A pinned or clamped system is generally not as strong as a threaded system. The 457's set-pins allow for quick barrel changes, and it's a cheaper system to manufacture, but how will those set-pins hold up after repeated barrel changes and other mechanical stress over time? Will there be wear or sloppiness? The 452's threaded attachment has already proven itself to be strong and accurate.
(2) abandoning the double lug design for a cheaper single lug design -- and shortening the bolt and action.
Again, the 452's top and bottom locking lugs are inherently better than the 457's single lug, in theory.
They add to accuracy by using two opposing points of contact to keep squareness in line with the bore axis.
Over time, you also get symmetrical wear on opposed lugs, unlike with a single lug.
The situation here reminds me of the Model 70 in '64 when Winchester went from controlled round feed to push feed as a way to reduce costs -- which resulted in pre-64 M70's becoming highly collectible.
Similarly, CZ's aim here was to reduce costs. That makes the 452 the pinnacle of their bolt-action rimfire lineage.
Combine this with the fact that the 452 has already earned legendary status for accuracy.
The 457 hasn't earned anything yet, other than through association with the 452.
So not only will the 452 Farewell Edition likely become collectible with time -- I think all 452's will become collectible with time.
I say "with time" because it will take a while for people to realize that the 457 is not a better rifle than the 452.