I agree. Importantly Space-X’s engines are actually cutting edge. They are the best performers man has made, so we’re not walking backwards. However, that progress was not guaranteed and if we stopped all space travel for fifty years there would need to be another monumental effort to relearn how to build rockets.

I play with CRTs as a hobby. It’s popular these days, but it will never be popular enough to manufacture another CRT. The last assembly lines closed a decade ago. The physics knowledge is there, and electronics have gotten better, but it would take many iterations to make a trinitron equivalent in another 20 years. The people who understood the magnetics (ie how horizontal output transistor and flyback transformer characteristics interacted with the impedance of the steering coils) are dead or retired. The same for the experts in mask manufacturing. We can figure it all out again and do it better than ever, but it would be a lot more work than if we had continued making them.

Again, it’ll never happen because they’re too big and require too much material compared to other display technologies. It’s just interesting how fast they disappeared when they were an integral part of human society for nearly all of the 20th century.