The pi device I have used to run the test, was setup when I wrote this topic
The image used for the above topic is Manjaro-ARM-minimal-rpi4-21.07.img and the kernel is the linux-rpi4 package.
Looking at branch-compare there is a couple of kernels - which relates to the different devices supported.
Without anything to back it - could it be that you accidently have installed a kernel for another device?