Yes, and now the U.S. mobile telcos are applying a completely subjective "reputation" "brand trust score", which sounds a lot like the Chinese social credit score. Oh, and they're charging a ton more for the privilege of sending a small number of texts, too.

I guess when you engage in price-fixing in the open and call it "setting a standard", then anti-trust rules don't apply..

Rate limiting is not the same as content filtering.

I promise you there is tons of actual keyword based content filtering going on. We had to build an AI just to detect which keywords different carriers block. Anything socially contentious, like "BLM", "election", "covid" increases the chances your message will get a 30008 error aka carrier-level content blocking. More disturbing is that plenty of carriers will also block messages but report them back to Twilio as delivered.

Does anyone know what year and date this started happening?

Sounds like something that should be challenged in court.