Well, the old Japanese Squiers from the 80s fetch the most $$, and they've been expensive for years, not just in the latest economic turbulence and price hikes. Sometimes it also depends on the model too - the 90s Venus XII is sought after; saw recently that prices on the older Stagemasters/Showmasters have gone up as well.
Reverb has some inbuilt costs for using the platform, afaik, so folk presumably bump up the price of what they're selling to offset that.
Anyway, everything's become expensive in the last couple of years *shrugs*, and people probably think they can recoup some life costs by selling stuff. Because of shipping/supply chain issues, this may have worked into the hands of sellers over the past two years, but we seem to be coming out the other end of that. Though wages aren't really climbing, hence the balking.
Still, I think we're past the days when you could get your MIM highway one Strat or Tele for $200-300. For Fender, certainly, the range has changed where Squiers have expanded so a CV is the highest spec, which can be in the $400s new, then the Mexican stuff follows on from that. Epiphone similar, there are (non-US) models which are 1k or a bit more. So this affects used prices too, I imagine,
Yet, I agree that some have an unrealistic idea of the value of their particular thing, then they find themselves sitting on it - often see listings that are months old.
If you want a good price, local classifieds are probably the way to go; the big sale platforms are generally the priciest.