No disagreement with you on the training, at best Peloton is a training aid. Or if all you want to do is a 30 minute spin class every day it's great for that. But if you know what you want, you can find other training on it as well easily enough. It's not a straightjacket, and people who lack imagination lack imagination outdoors on a road bike as well (although being outdoors often inspires on its own, but that's a different conversation.)
On the price--I think you're probably just a bit out of touch. In the US, at least, used bike prices are running more or less equal to original sale price since early 2020. What with the worldwide bicycle shortage and all. I think that's finally coming down, however, now that new bike inventory is returning to retail and you don't have to wait 6-12 months for a bike (depending on what sort of bike you're looking for). In a best case scenario we soon have a bicycle glut and all bikes are much cheaper, but even if that's in our future, it's not the present yet.
*edit to add, here's a 7 year old Giant TCR on a resale site (not your best price, but a good barometer) for $2300 USD. Looking on facebook I can find a 2006 Giant TCR for $600, but then I have to travel/ship.
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