Proton collaborates with spy agencies. They want it to have more of the users who aren't using Gmail.

Every company has to collaborate with spy agencies. Majn difference vs. Gmail or most others is for email and files Proton have no information to give except the IP you used (really hard for users to mask), and they seem to deny VPN activity logs 100% of the time.

If you're a criminal that has nation state actors after you I'm not sure what service I'd recommend. For most every other person Proton is way more than private enough.

https://proton.me/legal/transparency

I think I'm with some of the other commenters in that there seems to be an oddly smelling smear campaign against them right now.

For non proton to proton messages, they can view the entire message that is sent and can store it or whatever. You cannot rely on some transparency report since there are gag orders and what not.