99.99% of the world lives in threat model 1; our goal as security minded people is to protect these people. These people want general purpose networked computers in their pockets.
0.01% of the world lives in threat model 2; our goal is also to protect these people. But these people don't get protected while also having general purpose networked computers in their pockets.
Both groups are civilians, and both deserve security. But they also have different demands; if Apple forced Lockdown Mode's usability restrictions onto a billion people tomorrow, a large percentage of them would switch to materially less secure hardware and software vendors.