Excellent topic. I have discussed similar topics on watch and stereo forums as well.

There is something classic about the simplicity of vintage lightweight bikes. If cared for, there is no reason those bikes can't run forever as there isn't much to break, and it is pretty easy to find replacement parts. Will that be the case for today's higher end bikes? Only time will tell.

Regarding cost. My take is, maybe really high end bikes have gone way up in price, but at the same time, regular bikes that people ride just for recreation are, inflation adjusted, more affordable than ever. When I was a kid in the late 70s, a basic heavy entry level bike store 10 speed might cost maybe $150 to $200. I remember admiring a bike, a Raleigh, I believe, that sold for $600 in 1979. Inflation adjusted, today's hybrid or comfort bike retailing for $300 to $400 with 8 to 24 speeds indexed is a lot more practical (and cheaper) for the average recreational rider than those cheap heavy 10 speeds of the 70s.

In addition to all the higher end road bikes, will the 80s and 90s era mountain bikes ever be valued as lugged steel framed road bikes of the 70s and 80s are today? That remains to be seen. They certainly aren't as pretty, but the frames and wheels are durable, and they are relatively simple to repair or upgrade.