Newer bluez is buggy. It makes CPU usage 100% randomly.
5.72
is working fine. Let's keep using it.
sudo pacman -U /var/cache/pacman/pkg/bluez*5.72-2-x86_64.pkg.tar.zst
I need to ignore upgrading bluez until a stable version is released. To do so,
sudo pacman -Syyu --ignore bluez --ignore bluez-libs --ignore bluez-utils