We have way more information stored on these devices than ever before. They want it because it's there, not because they need it. For example, the first mobile

We have way more information stored on these devices than ever before. They want it because it's there, not because they need it. For example, the first mobile phones, could only store 10 text messages, you'd typically delete them after reading. Modern phones store years of messages, so the governments want that. Further back, we communicated in person or the phone, for which there was no record of what was said (unless actively under surveillance). Now these conversations are stored forever Facebook messenger/What's app etc. One solution would be to simply automatically delete messages after reading.