AMD pstate=active gives lower idle on Arch vs OpenWrt ... why?

Installing and Using OpenWrt
1

If I boot into Arch Linux on a mini PC (AMD Ryzen 7/5800U) with amd-pstate=active under linux-lts (currently 6.6.48), I find that while idle, most of the cores sit at 400 MHz. If I boot the identical hardware into OpenWrt snapshot which is currently on the same 6.6.48 kernel with the same kernel parameter for amd-pstate=active, I am finding that while idle (all daemons disabled) the cores sit at 1384 MHz.

Both distros are showing the same values for:

# cat /sys/devices/system/cpu/cpufreq/policy0/scaling_governor
powersave
# cat /sys/devices/system/cpu/amd_pstate/status
active
# cat /sys/devices/system/cpu/cpufreq/policy0/scaling_driver
amd-pstate-epp

I am wondering what kernel config differences in Arch's linux-lts might account for this.

Our linux-lts config
OpenWrt's config