Audio gear is remarkably wasteful, because of terrible design decisions.

A classic stereo amplifier from 1975 or 1980 will still provide useful service and is often highly repairable (service docs, equivalent parts available).

When they added video functionality, it became a disposable timebomb. Nobody wants a pre-HDMI AVR, or one that doesn't support this week's HDMI and spatial audio formats. Meanwhile, the newer features add huge complexity and custom parts, and often awful user interfaces dependent on a remote or even connection to a TV to use fully, so they're poor choices even if you just want to use them for stereo audio.

On the other hand, if you want to fight with it, I'm pretty sure that if you built an empty Goodwill 500km from human contact, inside of a week, three probably-functional but obsolete Sony, Pioneer, or RCA AVRs would spontaneously appear. They're freaking everywhere.