i5-12600K with 4 out of 16 threads at constant 100%

Why does my CPU behave like that?
I run "nothing" beyond a bunch of Chrome, Brave and Edge tabs - I love my tabs - but the total usage is nowhere near what I perceive to be at the limits of my system.

I had planned to add a picture of the CPU usage but I am not allowed.

I also have 64GB of DDR4 and I rarely see it use anything above 32GB and it annoys me that I get stuttering video or games when there is SO much more it could utilize.