I wanted to like PM and became a visionary subscriber years ago. But I left after painfully discovering that their web client (which was the only option at that time) was just not built for busy inboxes. Even today, many of the original pain points exist.

The UI is still clunky, and paging through the inbox is really terrible. Now they will promote their bridge to allow you to use Outlook or whatever, but that's not a solution for some of us.

I assume their need for revenue is what drives the features-before-improvements approach, but I know it is costing them some potential customers.

Nowadays I only use PM for special occasions, such as needing a temporary private email conversation with someone (who also sets up a new temp PM account).

I have found Tutanota to be much better in terms of usability. I can't speak for their security quality compared to PM, but honestly, unless you're only communicating with other local users, your emails are unencrypted at the other end. So the whole encryption topic is moot in many cases.