I think, the more extraordinary the claim is, the more proof is required. And I’m with you, I’d normally be incredibly skeptical of a substack post from an author I’ve never heard of before, who writes as egotistically as this. But there is just no extraordinary claim in this article. Only a very very ordinary claim that should be believable to any person who has ever owned a cell phone:

SIM farms are normal, common things that exist all over the place to allow messages from far-away senders to be sent as if they came from a local number.

That’s all the author is asking us to believe.