Keep in mind, that Brax uses misleading YouTube videos and their devices are as secure as my 2017 Redmi with LineageOS and a non-relockable bootloader (which I use with caution).
Also: mobile linux doesn't even offer the security of Secure boot on laptops (maybe Purism does, as they have a good track record on their laptops).
Please don't be an idiot, use GrapheneOS as it is the only security focused mobile OS.