I think the major fault with this reasoning is that the exact same solution has been proposed many times for e-mail, going back decades, and has never come even close to catching on. I think that applying a cost - whether time or money - to producing phone calls would fail for the same reasons. Namely, the significant difficulty in making significant changes to the telephone system (e.g. changing requirements to make a call, something which has almost never happened in the history of the phone system) and the lack of incentives for the telcos to do so, considering that they make termination fees off of these spam calls.
Yes, but these charges were all imposed by the telco for end users, and special arrangements for large customers have been the norm since the AT&T breakup. There is no facility to ensure that _all_ calls have paid a fee because many customers have, for decades, had arrangements to make calls with no fee required, and in general there has been no reason for a telco to have a mechanism to monitor another telco's billing practices.
In other words: yes, and many people also paid for their email accounts for some years. Yet here we are...
