And what advertising is that precisely? No data ( emails, passwords, drive files ) were shared with the authorities. So the data is still secure and private.

As far as I can tell they haven't falsely advertised.

I'd give them bonus points for transparency ( publishing how many court ordered subpoenas they receive on a yearly basis ) compared to other companies that don't.

Other companies which are prominent in the privacy/secure email scene face similar issues.

E.g.: https://www.internetsociety.org/blog/2021/03/enough-is-enough-what-happens-when-law-enforcement-bends-laws-to-access-data/

I think you're mixing up anonymity with privacy. It can definitely be more anonymous, but you would need to take steps for that yourself ( Tor, VPN, ... ).

How though? They advertsize themselves as the privacy-conscious Google alternative which they very much are. Idk if I've just not been exposed to (their) ads, but do they make all kinds of unreasonable claims like being outside of all legal jurisdiction?