Idling damaging the torque converter

Had a buddy claim that if I idled my automatic I’d damage the torque converter cuz it’s spinning and fighting the engine, heating up etc. Apparently this makes his manual superior because in neutral it’s fully disengaged.

Is this true, and even if so is it actually doing any measurable damage to my torque converter? I figure they are both doing just as much damage if anything considering there’s still all the friction in the gearbox.