One of the reasons Apple went to their own ARM based SOC processors is greater power efficiency. They are not categorized as mobile processors versus desktop processors anymore, they can be used in many products. What you’ll likely see is that the thermal design in the upcoming larger iMac will be more efficient in bleeding heat away allowing lower temps when doing heavy computing tasks. Some of the testing of the MBPs was showing them running up to 106 C peak. When I think about the Intel based 27” iMacs they were just big screen laptop adaptions using mobile processors and GPUs. Now with the M Pro and M Max being utilized you will be doings things as well or better then the best Intel iMac Pro line that was discontinued with far better thermals. Can’t wait to this products arrives.