Sure, you can find a nice old 1990s frame in an attic. But it probably has rim brakes, and in some countries you can no longer find replacement pads from a local bike shop, only special order, and rim-makers are gradually discontinuing high-quality rim-brake rims. It probably only fits an 8 or 9-speed cassette, and both Shimano and many local bike shops want users to upgrade to 10/12/whatever speed. Product churn alone is forcing the industry in a troubling direction regard of we retro-grouches would like.
I'm surprised to hear that in some countries rim brake pads are getting harder to find. What sorts of countries are those? Disc brakes are pretty fancy all things considered, are you talking about high-COLA hilly places like Norway or Switzerland?
> Disc brakes are pretty fancy all things considered
This hasn’t been true for a while now. I have noticed that many – if not already most – of the Chinese BSOs at hypermarkets have disc brakes installed.
I find it hard to believe, but if you're in one of these countries, you can just order brake pads by the dozen on AliExpress for a few euros and you're set for the rest of your life.
This was in central London half a decade ago, and one piece of mind that I had when going for these types of bikes: no one wanted to steal them. I had yuppie friends who would fork out 1-2k on a new bike that they were too afraid to scratch to actually ride, and it would be stolen within a few months of its purchase. My bikes? I would leave them carelessly chained to some weak fence confident in the knowledge it would still be there when I came back to it.
There is freedom in cheapness.
Having worked/volunteered at multiple bike co-ops, I have never and will never buy a new bike. Often perfectly good if cheapish frames will get scrapped because there's so many donations coming in that can't find buyers.
I ride hard and fast, and I don't get passed even by the MAMILs on their $9k S-works riding my $40 steel Univega SS conversion. You don't get much by trying to shortcut your way to a faster bike with money. It just takes time to git gud.
My own personal budget is never to spend more than $450 on a bike before repairs (which I mostly do myself, so the only remaining expense is (used) parts), and even then, I'm going to make sure it's steel alloy frame with great geometry, disc brakes, and at least 2x8 drivetrain. My craziest expense was a vintage Marin MTB (top of the line in its day) with some blown but nice shocks that was $300, but I had to send in the rear shock for a full rebuild so more like $425.
One of these days I may spring for a sweet, "well-loved" Rivendell frame or something similar. Planning on snapping up some kind of All-City soon since they recently announced they're discontinuing that brand and everyone seems to looove the Space Horse.
If you don't have the time to do all that research, there's quite a few online communities open to "is this a good deal" type posts who can help guide you to find a used bike that will work for your needs and inclinations.