So (still trying to understand exactly what's what)... those companies are the ones providing connectivity to the actual scammy robocallers? Or what is it that they do?
The protocols are meant to allow tracing which network originated a call - at their root is an attestation by the network that a call they are originating for one of their customers is allowed to use the number in caller ID. If you're a network who wants your originating calls to be carried across other networks, you can't just set up a promiscuous attestation system that allows your customers to just slap on any random caller ID that they want, or else you'll get blacklisted real quick.
... to make tracing easier
We could always trace the calls - you just had to ask each telco in the path to provide those details. There realistically wasn't any enforcement to do that though.
Telcos are not clueless or powerless. They can put pressure on international peers to not send spam, but have no incentive currently. No real telco wants to lose partners.
so, due to not taking mandated security measures thus allowing blackhats into your system, [company] is banned from the network.