Broadly, in the US, the Federal Wiretap Act of 1968 still applies. You're going to have to convince a judge otherwise.

Yes, perhaps broad dragnet type of might be scoffed down by some judges (outside of Patriot act FISA judges ofc)

I would warn you about the general E2E encryption and encrypted at rest claims. They are in-fact correct, but perhaps misleading? At some point, for most, the data does get decrypted server-side - cue the famous ":-)"