That’s not true. It was just last year that some of the Ryzen 7000 models were burning themselves
I think he was referring to “back-in-the-day” when Athlons, unlike the competing Pentium 3 and 4 CPUs of the day, didn’t have any thermal protections and would literally go up in smoke if you ran them without cooling.
Some motherboards did have overheating protection back then though. Personally I had my Athlon XP computer randomly shut down several times back then, because the system had some issue, where fans would randomly start slowing down and eventually completely stop. This then triggered overheat protection of the motherboard, which simply cut the power as soon as the temperature was too hight.
When I started using computers, I wasn’t aware of any thermal protections in popular CPUs. Do you happen to know when they first appeared in Intel chips?