I have switched to Spark email client on my Android 8.0 phone. I like it but for one issue. The User Data shown keeps creeping up even though it is only supposed to cache emails, not permanently store them locally. Pushing the Clear Data Android option in storage would force me to reenter the account info etc.. Not a great solution.
I have also sent this question to Spark support. If I get a solution from them I will post it here.
One of the features I like about Spark is that by default I get a notification of the email with options to delete or archive it, etc. without having to open the client UI. Kind of neat for a freebie.