The problem with their point is that it it's a fair-weather argument. It sounds perfectly reasonable in a world of good-faith actors, and a checked and regulate

The problem with their point is that it it's a fair-weather argument. It sounds perfectly reasonable in a world of good-faith actors, and a checked and regulated law enforcement, filled with upstanding moral officers. And even if you trust the current government, how can you trust a future government to continue acting in the best interest? Maybe abuse won't happen today, but what are your guarantees that it won't happen in the future? Also, we live in a world where there are still plenty of totalitarian regimes. If, for example, Apple develops this capability and give it to US law enforcement, every single totalitarian regime out there is going to demand access to the same thing for their law enforcement, and then we know they are going to abuse it.