"One solution I see (even though I'm technically inept) is some legislation that forces ISPs to block encrypted traffic, unless the user is checked against some license - and that license comes with a mandatory "law enforcement access" details."
I'm glad you qualified your opinion as inept, at least you get one point for accuracy.
Concepts of this scale do not neatly translate into a worldwide deployment of a single (complex) technology. For reference, government departments don't even understand their own rules (HMRC) and they can't even implement an age verification check for porn without cocking it up (pun intended).
Just so you know, it would be *extremely* difficult to deploy in a single large company, let alone all large companies, excluding private citizens, across the globe, meeting all legal requirements for all nations and still deliver the intended goal.
In the real world it's as close to something that is impossible that I can think of, and that includes matter transformation, free energy and teleportation across vast distances.