It is difficult to make predictions that far into the future (so I won't). But I will provide some perspective specifically around CRTs.
Look around YouTube. There are several people who enjoy resurrecting and restoring old television sets from the 1950s onward. While not as large as the video arcade collecting community, they still find a way to 'make it work' between donor chassis/tubes, NOS tubes still a plenty on eBay and such. While I have no sentimental attachment to a first generation color television set from the 1950s, I can appreciate their fervor in brining them back to life in the same way I do a G80 game. 70 more years from now when a few more generations have cycled through, you may eventually see the hardware diminish or dry up as a function of part availability and general interest in the platform will slowly fade simultaneously. Nothing lasts forever.
On CRTs specifically though, many of those 1950s-era tubes have gone to air. Not because they were necked but because the seal between the gun assembly and the glass develops natural leaks over time. There isn't a thing you can do to prevent it as time marches on. What happened by the 1980s and 1990s? They had that problem solved and rocked out some CRTs that made the ones from a couple decades ago look primitive in both reliability and longevity. The downside to that is they indeed used toxic chemical like lead to make leaded safety glass, which is why tubes are so heavy but also why they have a beautiful, crystal clear transparency to them. There are probably other trace elements used in them that would be either illegal or prohibitively cost expensive from an environmental standpoint today even if someone had to cash to want to reproduce them. And sadly, as 'good' as technology is today, you will likely never find a more optimal (or equivalent) material substitute for making CRTs unless you invested tons of time and effort into R&D. Likely won't happen unless AI can save us there (skeptical IMO). The equipment, rigs, manufacturing processes, operators, engineers and everyone else who worked for Zenith, RCA, and several similar companies are either deceased or the assets have been sold overseas and possibly scrapped by now. Even though I would love to say 'it can happen', the barrier to re-entry on CRTs is very, very high. And even if you were able to make something that looked and felt the same, who knows how well they would last long term (e.g., would we 'revert' to 1950s era, short life tubes)?
Moral of the story: As long as we're all alive and breathing, preserve as much of the original hardware as possible. CRTs are delicate and easy to break. While they do take up a ton of room for storage, you can go through a couple dozen replacements quicker than you think. Have fun along the way. Let others enjoy the fruits of your labor. That is the best outcome you can expect.
