every company is legally obliged to work with law enforcement
Of course. Proton doesn't really have a choice whether or not to fulfill law enforcement's requests.
However, Proton absolutely does have a choice when it comes down to the scale of their cooperation with law enforcement, as well as the enthusiasm behind it.
In my opinion, in these two metrics Proton very noticeably falls behind most of their competition. That's why I wouldn't use it for security or privacy.
Plus - Lumo AI? Seriously? What sort of privacy-focused company invests into an AI chatbot?
It's definitely better than GMail. Everything is. But if you want serious privacy and security... Yeah, no.