And I wasn't contradicting that point (or misunderstanding it). Most companies have some form of proxy and can also control your ability to use a VPN as well.
There's still a sizeable chunk of work from home workforce, which also defeats the purpose.
Managers have learned to look at output to determine productivity (at least, the smart ones have).
20 years ago? This would have been useful. Even 10. Now? Not so much.
Maybe for kids trying to be sneaky around parents, but even parental controls have come a long way.