I concur, I have a similar setup. Most expensive computer I've ever owned. It just throttles at the drop of a hat. I worked through it all with the apple techs, jumped through hoops for many hours and provided detailed diagnostics. They dismissed me with "throttling is normal, there's no problem".
In the real world, my 2017 MBP performed better just because it didn't throttle. Ridiculous.
As for the supposed 'Low power mode' in Monterey - I'm not convinced that isn't just turning on throttling manually.