The issue is not whether there is an alternative or not. The issue is convincing someone who uses Gmail to stop using it, and change to another service.
That's why I don't believe in switching services, an email provider should merely be used as an email provider and have all the desired features (privacy, encryption) built on top
More like two people having a conversation in the street, except one of them is screaming every word and you're just asking to please tone it down a bit, which is too much to ask for that person.
Mail is not that private, that is not the point being argued, and why I offered the street conversation example. From the moment you communicate with someone else, you've lost control over the information.
But there's a huge difference between that, and having every word you write plus all the info that can be inferred from that, recorded, stored forever, analyzed and re-analyzed, sold, exploited, misused, etc, by a hostile unscrupulous advertising company or its partners.
IMO, you’re probably better off with Google or to a lesser extent Microsoft, as their model is about selling ads based on your information, and hoarding your data for competitive advantage.
I assume that your cellular carrier and cable company are monetizing any bit of data they can capture and selling it for pennies to all sorts of parties.
There's a reasonable compromise to be found to live in a modern digital society. Otherwise, just move to a deserted tiny isolated island in the Pacific. One with a bit of higher ground. Climate change, et al.