I know there's MailButler for Apple Mail, at least, and you can script just about anything you like with a mail client like mutt or mu4e. I imagine there's a plugin for Thunderbird derivatives, though I haven't looked. Be the hero you want to see in the world!
I use the desktop version of Outlook with the following apps, Doodle, Zoom, Trello and while I haven't taken a deep dive as of yet Mailbutler it appears you can automize a lot of your daily email task.
I think we're also underutilizing Teams but that's a fight for another day. it appears you can automize a lot of your daily email tasks.
i've tried a lot of applications, but always came back to Mail. I use it for personal and business purposes. I also use SmallCubed Mailsuite & Mailbutler extensions. Having said that, maybe Airmail or Postbox might satisfy your needs.
Focused on email productivity, which for me is part of personal productivity since emailing plays a large role in my job. I use Mailbutler mostly to keep track of my sent emails, tasks, and follow-up messages. The nice part about it is that it has an Analytics section where I can keep track of how productively I have used certain features (displayed in saved time, usage, and performance). For the majority of the features, I have a graph displaying how well they have performed.
As a freelancer, I do this pretty often, especially with emails. Those having important information or important attachments I save them to Evernote. I use this free plugin, Evernote Exporter from Mailbutler, and until now it worked wonders.