pmOS is insecure as fuck compared to Android
They lack the boot integrity features, the OS is a poor imitation of Android that insists on doing things differently and not learning from what Android figured out ages ago. pmOS and other fd.o distros are nice if you wanna tinker; if you want smth secure, Android is basically best you can get.
Android has a userspace designed with security in mind, fd.o has security as an afterthought (that's why eg. flatpaks are the state they are in).