I switched to Protonmail a month ago. It is patently inferior to gmail. Every day I get annoyed by some weakness in the UI that google had apparently just always solved without me ever having to think about it. For example, reading long email chains in the proton UI is horrific. I don't know what google did that made it natural to read and proton does so badly, but it is painful to read these long chains of emails. Another example is log emails from my servers are getting grouped together by Proton. Gmail had sepearated the logs into separate emails in a very natural way. These small annoyances add up and I'm not having a fun time right now with proton.