[Proofed]

I think you are right there are a finite amount of serious historic pistols in the world and also a finite amount of people who know the difference and have the resources to collect them, that number is dwindling also. The amount of time and effort to get up to speed on any type of advanced education on Lugers is measured in years and requires a considerable effort in time and money.
I don't think the interest will go away per say but it may very well go to even less collecting to even more speculating in the coming years. That opens up more room for trolls and bottom feeders into the mix, what a shame.
As the education level drops so will the investment value to a certain extent. I've never bought a luger with the thought of making money there are other ways to do that, as opposed to relying on a volatile collector market. Don't get me wrong there are people who maintain collections of anything who buy sell and trade to continually upgrade the collection over time, that in itself is an artform that requires much discipline.
Buy what you like, like what you buy, don't buy because someone else says you need it for your collecting direction, what makes you happy will probably just make the family around you Wonder
when you finally go away for good.
My 2 cents.