I left my Mac Studio running at 100% CPU on all cores for 14 hours, and the case ended up noticeably warm to the touch. It is possible!

I recently installed an app to manually activate the fans on my MacBook Pro M1 Pro as I've never been able to trigger them over the past 4+ years. Just to check whether the fans even work (they do).

Try increasing to 10 cores. Works on my m3 pro.

https://xkcd.com/1172/

Honestly m1 was very cool no matter what workload you threw at it but at this point m4 max does get pretty hot even with just web browsing.