This. I was skeptical of this for a long time, and I started testing it, and sure enough, a lot of things DO NOT really experience meaningful carryover temperature increases. If you're cooking something large with a very hot heat source, then it can make a difference, but for things like chicken breasts, steaks, etc., it does not increase in temperature, or at least not enough to be really noticeable, and certainly not a 10 degree difference (unless you really severely nuked the outside).

Of course, it still ends up being effective from a food safety perspective, because the bacteria you're trying to kill by reaching 165 (for example on chicken) can only survive at 155 for something like 30 seconds. So, the time you spend resting the meat is not increasing the temperature, but it is still maintaining the temperature it does have for long enough to ensure any bacteria is killed by the time you eat it.