I believe that there's an inter-generational change happening in the world of printed comics, driven by real-world economic and technological factors – i.e. increasingly expensive housing, growing economic disparity, and cheap streamed media.
On one hand, home ownership rates are falling and rental properties are shrinking in size. On the other, books, music and video are now generally cheaper to purchase or stream electronically compared to buying physical copies. The result seems to be that kids are just less interested in acquiring "Stuff".
When I left home as a teenager, I already had a collection of comics, a small but beloved library of books, and two boxes of vinyl records. Over the next 20 years I increased the comics and books, replaced the vinyl with CDs, and added a DVD collection. I spent three decades acquiring shelving. I purchased my first home at the age of 26, it had four bedrooms and a large living room, and I spent my weekends building shelving and filling it with "Stuff", the proud confirmation of my disposable income.
But kids travel light now when they leave home. Gone are the boxes of CDs and DVDs, and gone too are the long-boxes of comics.
An increasing percentage of Americans are fighting just to pay accommodation, education, and health-care. They don't have disposable income, and they don't have large empty houses to fill. They don't amuse themselves buying complete runs of Daredevil (Vol .1) on eBay. Instead they sit in their "tiny homes" binge-watching Rick & Morty on a tablet (when they're not working their third job at the supermarket).
Even old-timers like me are changing habits now. I'm increasingly relying on Spotify and Netflix, and buying a CD or DVD is a rare event now. I've given up on buying new comics (there were too many of the damn things). Mind you, I still buy books on paper, and that is unlikely to change.
It's not over yet though. eBay shows me that there's still a market for the top-end collectibles. There's still plenty of young professionals who aren't having kids, and who can fit some cool "so retro!" comics into their budget (and their stylish two-room city apartments). And of course, there are old guys like me who still have that addiction to "Stuff", trying to fill in the last few gaps in their collections, fooling myself that "completing" the collection will somehow make me feel "complete".
Not sure what I'm gonna do with my collection when I die though. My kids don't want it!