I have noticed the prices for vintage bikes dropping over the last 2 years or so. The big Italian names and the fancier British marques like Ephgrave and Hetchins seem to be holding their price but decent factory build 531 framed Raleigh’s seem much more reasonable now.
I wonder if the trend for people buying a vintage bike just to ride L’Eroica with their mates is tapering off? I’ve also noticed that here on the hip streets of East London vintage road bike seem to have been replaced with modern machines
I reckon there's a number of factors at work, of which demographics is a significant one, but not the only reason.
With the proliferation of lower-budget CF and the cheap end, mass-produced imported aluminium frames, you no longer need to pay a premium for a 531 frame if all you want is a lightweight bike and are not bothered about aesthetics. Budget new bikes can be a lot lighter than budget "gas pipe special" steel bikes ever were. Most modern road bikes both in CF and oversized AL tubing, I regard as hideous looking things and I would never buy one, but clearly a lot of riders
are buying such bikes from major retailers, no doubt often with the tax incentive of C2W sweetening the deal.
It's easier to run something new with no mechanical wear and replace it every couple of years than it is to constantly maintain an older used machine which already had wear present when purchased, especially for the mechanical numpty who has to visit their LBS for every problem that occurs and incur labour charges. It's a bit like running a brand new car and changing it every couple of years.
With things like L'Eroica, maybe people do it once and then get rid of their classic bike afterwards? Or they buy one classic bike and stop at that, rather than owning multiples?
There's a generational divide. If I consider the bikes typically taken to my local watering hole, most of them are cheap-ish, modern bikes, often sloping top tube hybrids, and flashy suspension MTB clunkers at the BSO end. There's a Galaxy and two Bromptons, all the owners of which are in their 50's or older. The age profile of the modern owners is generally much younger than the classic riders. The youngsters who have only ever ridden the junk BSO's with 2" knobbly tyres have no appreciation whatsoever what a decent Reynolds frame is like to ride, and for them clanking along the road on a heavy, energy-sapping full-sus BSO is as good as cycling is ever going to get!