2fa and those services are different. LLM api calls are relatively costly and in demand so they must have a decent barrier of entry so people couldn't just spam

2fa and those services are different. LLM api calls are relatively costly and in demand so they must have a decent barrier of entry so people couldn't just spam automated accounts with automated requests to use the app for free. There are systems that abuse that and even existing API integrations are being abused by proxying and using for other purposes if they are free and don't have good security. Any place that wants to defend against bots can't trust those phone numbers.