ProtonMail Complied with 5,957 Data Requests in 2022 - Still Secure and Private?
(restoreprivacy.com)
Never forget every email that leaves Protonmail to other email providors are not anymore secure or encrypted as using gmail or others.
Second no one can certify that incoming emails and meta-data can't be read and recorded to a ghost mailbox before getting encrypted. you have no control on what happens on their servers
privacy shouldn't rely on trust