Sure there's a bunch of custom steel bikes and other production steel bikes out there, but these numbers are nothing compared to what they were back in the day when all the frames were made of steel .... I think Classic & Vintage folks will be stuck ogling bikes from the '50-'00
It is sort of a natural process, and there are parallel worlds. WW II fighter planes were ubiquitous for years after the war. Vast yards were full of them being bulldozed and torn apart for scrap — the equivalent of the dumpsters and the land fills heaving with CV bicycles. Some of these fighters continued careers in third world air arms. As time went on, survivors were picked up for collections anywhere they were found sitting — rotting. Nowadays they are being pulled out of the sea, picked off glaciers and dug out of swamps. Mega-heroic efforts are made to reconstruct these relics in ways that would have been unthinkable decades ago.
At the same time, jet fighter aircraft are largely being overlooked for a number of reasons. Not many are being flown in displays, and I’m thinking that an F-86 Saber is not going to receive the same riveting attention as a Merlin powered Spitfire. The very sound of that engine sends hearts racing.
Steel bicycles will become much more a niche interest. Diminishing stocks and parts will be commensurate with protracted restorations that will include replacing tubes. Exact replica frames and components will appear in the same way as classic motorcycles and even aircraft. Collectors will have smaller collections. Collections will attain an intrinsic value that will function as hedges against inflation. Vintage steel buffs and investors will be few. But, as you suggest, the CF niche may be even thinner. Thinner in the same way as there are fewer owners of F-86’s, Mig 17’s and F-104 Starfighters than P-51 Mustangs and Corsairs (that are still in competition racing).
Anyone who doubts what can be done to produce exact replicas of machinery can do a bit of research. Somewhere on YouTube there is a starting party attended by a large number of Vincent fanatics and their families. These are talented and skilled people. A group of them helped one their group to construct an exact replica of a Black Shadow* — 90% original parts. Even the carburetors were built from scratch. There may every reason to believe that if you are young enough you will see a new 2050 1965 Cellini in new, exact, replica Record gruppo. The end of classic and vintage as we know it. I’ll have a late 30’s Bates road racer, please.
* I saw this machine in Vancouver about a year ago — a stunning accomplishment.