Actually GPUs used for mining are typically undervolted to keep power costs down, and by running them 24/7 there is less thermal expansion and contraction so they’re not expected to fail at higher rates than other GPUs.
Source: I used to mine ETH years ago on used AMD GPUs when that was still profitable. From perusing mining forums this is still standard practice. I eventually sold all the GPUs and all of them worked flawlessly.
Doesn't really matter. Running a card 100% 24/7 is still harder on it that gaming a couple hours per day.
GPUs are relatively reliable, but fans less so. The failures are usually an early death of the fan, which can't be replaced without strapping something else to the shroud with zip ties or watercooling it.
Miners aren't usually impacted because the failures happen after several years. It's the downstream buyers who lose out and then associate the brand with premature failure.
Source: I used to mine ETH years ago on used AMD GPUs when that was still profitable. From perusing mining forums this is still standard practice. I eventually sold all the GPUs and all of them worked flawlessly.