Yeah, I do not see how stopping the spoofing (which I am all for doing) would be anything but a minor inconvenience for them.
Ideally, the telco would implement these block lists, but also ideally, they could be traded around like web ad block lists for individuals to load on their phones.
I think we all know scam calls are a serious source of revenue for carriers, so they will need to be led to this conclusion by force.
None of that happy future would come without true caller id, thus the resistence from carriers to fixing spoofing.
Why would they be a major revenue source? The carriers make their money from normal users, not dodgy call centers.
Right now, an actionable report really needs a traced call, which is hard to actually make.
Certainly, it doesn't get you right to a chargable person, but it gets you a lot more than today.
Ideally there would be a warning that a call does not originate locally, routing the call through a local representative would generate yet another signal that you might be able to close off, including the possibility to declare the possession or hosting of certain gear illegal. You'd have to maybe do some pattern matching to spot problematic numbers and/or have a place to report them easily.
If the will was really there I'm pretty sure this problem could be tackled.
Anyone can easily buy European bank accounts opened with fake IDs, or money laundering services where you're provided an IBAN and receive a % of the money sent there to your cryptocurrency wallet.
Want a fake passport good enough to travel with? No problem, will just run you a 1000 euros.
Probably, but not with any of your proposed methods. I have talked with some SMS spammers and none of what you proposed would affect them. And for SMS spammers these inconveniences are a much bigger part of the cost of doing operations than for a company which needs to have employees in a call center. They have to spend a lot of money on buying new SIM cards as old ones get blocked.