This guy can be pretty harsh at times, but he’s clearly very knowledgeable..
However, not all providers have a recent review, and his priorities are skewed heavily to the “paranoid” side of the tech world. For example, he considers being able to mail cash to a provider a significant pro. The overwhelming majority of users aren’t mailing cash to pay for their email.
Overall, it’s good info that’s worth sharing.
I use K9. It went through a rough patch a few years ago with the UI, but it’s much better now. Mozilla is involved and K9 is in the process of becoming the Thunderbird app.