My understanding is that refurbished GPUs from e.g. crypto mining are something people are warned away from, because they've often been run into the ground. Are AI usage practices different?
No, this wasn't the case. While there were never comprehensive studies various tech media purchased these cards to run testing and found that, other than scammers, they all performed to expectation.
Electricity is a moving part btw, electronic components do wear and tear
Even if it say, halved the life span of the chips, that is still far longer than what most people would ever use them for.