I think one of the real dangers to the future of the hobby is how hard it is to stumble upon good, old dumps these days. Most collectors got into it as a kid finding an old dump in the woods. Now there are still plenty of dumps in the woods, but they're full of slicks from the 50s and 60s and even when those bottles are 100 years old they'll still be boring. I still see a decent number of collectors at shows around here who would qualify as millennials (late 20s/early 30s) though, so the hobby shouldn't be dying out on a large scale in the next few decades - not like stamp collecting which is in a really dire state right now.
I disagree that young people today are uninterested in history and instead preoccupied with selfies and video games or whatever. People say the same sorts of things about every generation, and with every generation it's true for some and not for others. The thing with millenials and post-millenials is that they aren't interested in the 19th and early 20th century the way the Baby Boomer generation was interested in that era, but they're fascinated with the 60s and 70s. I think in general people are interested in the history of the era which came a few decades before they were born, in which it still seems familiar enough to have grown up around the remnants of that era and heard stories from their parents and grandparents about it, but is still far-removed enough that it feels like it has some sort of romantic mystique to it and the elusive sense of having been a better, simpler time. Remember how popular that old-west style font was in the 50s and 60s? Now modern graphic design is taking heavy cues from the 60s and 70s. Someone in 1960 would dream about what it would be like to go back in time to 1890 and be a cowboy. Millenials don't want to go back to 1890, to them 1890 is a very foreign world that they have little relation to. But they definitely daydream about what it would be like to go back to 1960 and be a beatnik.
We aren't going to see a disappearance of antique collecting. But we are currently seeing a change in what is being collected. These days it's mid-century stuff that's popular. Mid-century modern furniture is popular among millenials with more money and condos to furnish. For those with less money it's smaller stuff; cameras, radios, postcards, that sort of thing. But that does bring us back to the lack of good dumps for kids to find, since someone who's interested in the 60s isn't going to randomly decide to start collecting ACL sodas, there has to be something to spark that interest.
The large collection does seem to be disappearing, but I have to wonder about how much that has to do with millenials increasingly moving to cities since that's where the jobs tend to be these days, and rent in cities being too expensive for the space required to have a collection. I wonder if millenials in small towns are also giving up collecting. I suspect that they aren't, but I really have no experience in that area.
I would agree that the lack of good finds in the wild might reduce the number of new collectors in the future . also here in Ontario there was a big boost to the hobby when all the dumps and bottles were found in Toronto along the waterfront . that generated a lot of interest and also allowed for there to be a lot more older bottles for sale at antique malls/bottle shows at reasonable prices
but the digging in Toronto seems to have quieted down ( although there might still be places to dig I don't live there ) and its not clear if there will ever be anything like that again in terms of the volume and number of bottles found
I also agree that some of the other hobbies are worse off , like train collecting . there was actually a train show here at the fair grounds last week but I've never been to it and honestly surprised its lasted so long .
stamp collecting also does seem to be popular with much older people , although its still a popular hobby there used to be a yearly stamp show here but I'm not sure if its still active , only ever at it once cause I heard there might be some old postcards there and I recall finding a few , but when I searched online the last one posted was from 2015 , so not sure if it happens anymore or not ?
I could also see vintage car collecting running into serious trouble 10-20 years from now as the baby boomers pass away or go into nursing homes and are forced to sell there 1950's-60's era cars . none of the younger people remember these cars and won't pay a premium for them like they did ( might be more interested in cars from the 80's or 90's that they actually remember ) ,
wonder what market will exist ? prices could plunge
I think everything has its time . But I have always heard that what loses interest will come around again in later years and be popular again . Who Knows . Seems the bottom has fell out of just about everything except for the high end items . I believe the older generations who collected so many of the vintage collectables are disappearing as time goes on . The newer generation cares nothing about the old collectables .
I have two Sons who care nothing about anything old that I have collected . My oldest son said to me one day that when I was gone him and his brother were going to get rid of all this Crap . I told them that before I kick off I was going to sell it all off and their Mother and myself would spend the money ourselves lol . I could see them selling a two or three hundred dollar bottle of mine for a buck in a yardsale !!