Running any intensive job immediately throttles the CPU to 400Mhz! I found this:
https://www.reddit.com/r/thinkpad/comments/pvb87e/thinkpad_p14s_gen_2_intel_fix_for_aggressive_cpu/
which sent me to https://forums.lenovo.com/t5/Other-Linux-Discussions/X1C6-T480s-low-cTDP-and-trip-temperature-in-Linux/m-p/4028489?page=40#5069052 which explained there are actual Fn keys for this!
Can you check something for me. Do:
cat /sys/devices/virtual/powercap/intel-rapl-mmio/intel-rapl-mmio:0/constraint_0_power_limit_uw