While this is certainly true, facebook, google, Microsoft, and a bunch of other hyperscale cloud providers still regularly dump hardware on ebay for great prices.
I was working for a big US tech company in the UK. They regularly use to give servers and computers for decommissioning/dismantling. Once I asked if I could get those servers and computers to give it to schools and students who could not afford to buy one. I was told that it is not legal to give company computer away. There are restrictions on giving company computers in the open market, even if it is free.
source: used computers trade in California
Afaik, in uk, schools and the likes need to get warranties for everything "donated" in an effort to not become an e-waste dumping ground.
Instead what they did with the old non-leased hardware was that they said we had to bring it back when we were done with transferring our old stuff over (wink wink). But of course this model is not possible with a completely different party.