For your wallet, yes. Do you have any information about the environment in which a card was used? Temperature, dust, air moisture were like in a home or there operated in an industrial warehouse? Fan bearing status after all these hours? Voltage applied? Stock BIOS? were they in an enclosure or in a sort of a case? Thermal paste has been changed? Ever been disassembled?
I would not trust a miner's card even if it was a gift.
Miners screwed the market over and now they want you to think that their used crap is such a bargain. Let them deal with their waste, don't help them.
As for waste: I very much hope it will not become waste. Why would you be advocating for that?
That would be even more true for cards owned by non-miners; most miners will operate at a large enough scale to use some best practices, which definitely isn't true about most people who buy GPUs for personal use.
I don't think there was anything artificial about the scarcity generated by miners; the demand was genuine. Scalpers are a different matter....
> And don't believe that a card that has been on 24/7 is safe to use
Are you claiming that it is somehow unsafe to use?