GPG was just an example. Other end-to-end open-source systems are more widely used like Signal are the same, not exactly easy to insert a backdoor into a system

GPG was just an example. Other end-to-end open-source systems are more widely used like Signal are the same, not exactly easy to insert a backdoor into a system that is a) open and b) completely distributed with no central key authority. Maybe it still misses the point because the FBI doesn't actually care about hitting hard targets. If that is the case that is pretty sad. Average crimes can be solved with average tools, we shouldn't be authorising access to phones and other electronic intercepts or access without crimes that go beyond average. You could argue the San Bernadino case was beyond average, and you would probably be right. But the perps knew that too, that is why they destroyed the phones after they were done, chances are they took other measures too but no one will know as they destroyed the devices. What is clear is not that these laws wouldn't make their jobs easier - they almost certainly would. But they aren't needed and that implementing them would have 0 effect on the actually hard targets that they in theory would be useful for neutralising.