[jauer]

IANAL but I do ISP compliance paperwork ~14 days out of the year...

Seems like Google could trip over the CPNI rules if they were using call data for AI training etc. Certainly if it somehow ended up used "for advertising purposes".

It's not so much FCC licensed as FCC reporting (Form 499, etc), though many states require some form of carrier licensing. In any case, Google's already had to jump through those hoops for Project Fi. E.g. if you search `"Google North America Inc." public` you should see a ton of filings about that.

SMB/Enterprise would be a interesting market for Google. That's a relatively high-touch market and I suspect they'd run into the same objections as Google's public cloud offerings with regards to support and hand-holding. POTS replacement (or even end-user cell service) is fairly low-touch & automatable by comparison.