That is not what I’ve heard from speaking to appliance repair techs, or builders/architects, or the Sub Zero owners I know with 15+ year old refrigerators that

That is not what I’ve heard from speaking to appliance repair techs, or builders/architects, or the Sub Zero owners I know with 15+ year old refrigerators that have never had any issues (except the ice maker, which is an inherently unreliable piece of technology). My guess is your friends aren’t maintaining them properly (they know they have to clean the condenser coils every couple months, right?) Either that, or they have those “integrated” models with no visible vent for the condenser, which of course will overheat the compressors and electronics.