Wouldn't solve the issue. You can have censorship with open source software and so long as there is a locked bootloader you couldn't easily replace the software. Also, even if the bootloader was unlocked the majority of people aren't technical enough to replace the software that is doing the censorship.
There is a fundamental contradiction between safety and freedom. The more you are in control, the more you need to know and pay attention too. Any guard rails necessarily limit your choice of path.
In other words, the price of liberty is eternal vigilance, and there is a lot of people who do not want to pay that price. They just need stuff done, no matter what.