That is the fundamental problem with email as a protocol, yes?
Zero knowledge inbox, externally audited code, a company actually caring for user privacy definitely is a win for me when the alternative is Google hoovering up your data. Is this what you meant by saying it is the next best thing?
I switched to Pipepipe from Newpipe because I wasn’t sure Newpipe was being maintained. Pipepipe has SponsorBlock.