Exactly.
When a new scope comes to the market and is somewhat scarce/uncommon then you can ask a higher price used or near new.
Once there are a heap on the market then you can no longer expect to get close to the retail price, especially if there is competition in the used market.
The fall in 2nd hand prices has nothing to do with the cost of manufacture, or a perceived out dated design.
Supply and demand, time on market, an updated version (atacr 7-35) or new competition will cause a drop in used prices (as thats what this thread is about) not competition that was already on the market for years, as that would've effeced the price from day one.