Blame crappy MacOS codec support or coding with the video conferencing software as all mbp run hot with those apps. Even my 2020 mbp 13 i7 10th gen with 10nm chip will run loud while using zoom.Based on the posts here and the Apple Support forum (there's a 200+ page thread about it there), it's a widespread issue with the MBP16.
People are 'fixing' it by disabling their CPU turbo boost and running only in clamshell mode with external keyboard and mouse.
That's unacceptable to me. When i pay $4,500 for a laptop, i expect it to work well, especially with modest, everyday kind of tasks like video conferencing. I want to have use the internal screen and an external monitor at the same time. I want to be able to use the keyboard, trackpad and speakers i paid for - not be forced to slow down my computer and purchase external peripherals to make it work.
You’re probably going to have to wait for ARM Macs.
I gave up and use my 2018 iPad Pro for video conferencing. At least it’s dead silent and has better mics and camera blows away all current mbp