Software freedom is about freedom of choice, not philosophically mandated security holes. You are free to take the GrapheneOS code and introduce a huge vulnerability in the form of a privilege escalation path from sandboxed apps if you wish, it is open source and you can easily compile and flash your own build.
Mobile phones store incredibly intimate data and are incredibly vulnerable to seizure. It stores my message history, pictures I've taken, so many other records that together would provide an incredibly detailed view into my private life. And it is on my person at all times, even through checkpoints where I have minimal protections against search and seizure like borders! This is not a device that I want a broad surface for modification of system software on.
Mobile phones store incredibly intimate data and are incredibly vulnerable to seizure. It stores my message history, pictures I've taken, so many other records that together would provide an incredibly detailed view into my private life. And it is on my person at all times, even through checkpoints where I have minimal protections against search and seizure like borders! This is not a device that I want a broad surface for modification of system software on.