I give 5 years, and the bubble will start to slowly leak. It won't burst but after 5 years the prices will get better. My reason is for age. A lot of kids now have little to no interest in 2d/old games. Our problem was everyone our age or in their recent 20's finally graduated college, got jobs and had money to blow. Well now everyone is getting older, starting families and needing money elsewhere. Shit will get sold off and prices are going to drop. It's kinda like how everyone gobbles up new systems to try and gouge, then interest wains, and people are left with wasted money. In 5 years if I'm wrong you can all come back and laugh at me, but I still believe 5 years is going to be the point it will start to drop.
Seems logical, and you could be right, but I'd like to offer another perspective. I believe it's in our nature to want to accumulate things. Whether these things are tangible or not is another story. Just look at the concept of gamerscore through achievements on Xbox. Some people refuse to switch from xbox to PS4 solely because of the potential of losing their gamerscore, or worse yet, the little number in your profile that indicates the number of years you have been an xbox live member. Status is very much tied to how much stuff you can accumulate.
Look at this very site. Post count and years of membership count for something (not arguing this point), but there's nothing to say that a new member with limited posts can't be as valuable or more valuable than a more established user. Take me for example. I've been on this site for the better part of a decade, but haven't really contributed a damn thing to the community. I recognize now however that this community is different than the community on other gaming sites. You're not circle jerking around a Nintendo cart because it has 3 screws in it instead of 5.
I'm not so sure that the nature of people will change. The only question is WHAT will people collect in the future? I don't think you were ever debating whether people would continue collecting period, but If we can agree that interactive games/entertainment will be popular, either through virtual reality, or some other medium, then I suspect collecting remnants of the history of that past-time will also be popular. If anything, the next generation is more apt to collect vintage games than we are given the abundance of information that will be available at their fingertips. When I started getting in to gaming, there was no internet. By the time I really discovered what the true gems of each console were, it was too late for me. I have a nice pile of games, but I have basically gotten to a point now where realistically getting each title on my wish list is impossible without being irresponsible.
However, the upcoming generation isn't incumbered by responsibility yet, and all it takes is a handful of zombies who must acquire all the RAREZ to set this perpetual cycle in motion yet again. It starts with what they know; PS1, N64, Xbox, etc...and then they are introduced to other consoles through research and reading and the need to get out there and get that next copy of Magical Chase grows from a want to a need. Look no further than the dude who came in here to drop $5,000 on a copy. No way that guy just woke up and suddenly decided to drop a small fortune on a game. That idea brewed and manifested itself in to something arguably crazy to an outsider. On a sidenote, I do believe he was mistreated here, but I'll leave that for another day. I'd love for him to chime in and tell us what lead him to that state. I am not judging him at all. I've been there myself.
I recall spending $325 on a copy of Eliminate Down for the Mega Drive; killer game by the way, and I am happy to own it, but I had to psych myself out to get to that point. Ever afterwards, I seriously regretted that purchase and felt like a tool for spending so much money on a game. In hindsight, from a value perspective, it has worked out for me in that Eliminate Down has jumped up in value. Will Eliminate Down hold is value in to the future? I'd like to think so.
My point is that great games, regardless of their age will hold their value. I also challenge you guys to come back to this post in 10 to 15 years and rip me apart if I can't even give my copy of Eliminate Down away at that point because nobody gives a crap out antiquated video games.