From the stuff I have access too physically (xeons(well gold cpus) and thread rippers) the intel stuff is much cooler until you really rag it, where as the threadrippers are just plain warm.

This isn't scientific, so I might be comparing big 64 thread monsters to smaller intel jobbies.

If anything Intel has become better with each newer generation. My 12700K idled at < 3W package power. My 13700K pulls even less. They have a lot of good stuff going on like not enabling the L3 cache if the CPU in only briefly awake, or dynamically resizing L3 if they can get away with it.

My Zen3 still pulls >25W at idle which is an absolute embarrassment.