Re: Well maybe
"Conventional POTS telephone communication was never secure and it's monitoring by authorities to prosecute criminals was always legal "when it was carried out under warrant
There's a big difference between targeted surveillance carried out under the rule of law and surveillance, targeted or not, by anyone who fancies doing saw. The difference is "rule of law" which is an essential component of a free society under the rule of law. And is there any way in which that freedom can be maintained?
"There is no reason to believe digital or other communications should not be monitored to convict crims or for security reasons."
No there isn't provided there are legal safeguards such as requiring a warrant obtained from a competent authority who has been provided with a sound basis for granting it. For avoidance of doubt a competent authority does not include other members of the investigating body or a politician. Independence of the judiciary is an important factor in a free society (which, BTW, is a reason that some of us look askance at the political shenanigans involved in the appointment of US judiciary).