“New Look” Outlook Shipping in October

However, it still lacks support for regular mail accounts (IMAP, Exchange, and POP)

Does it? (Maybe you’re only referring to this preview?)

I tried adding a Gmail account and it even integrated with Google’s OAuth flow.

Then I tried the “Not Google?” link, and it showed me a selection of:

Office 365
Outlook.com
Exchange
Google
iCloud
Yahoo! Mail
IMAP/POP

If I hit that last one, I get a more complex form with fields like incoming/outgoing mail server, port, etc.

That said, I wouldn’t use Outlook for stuff outside the Exchange world. Its strength is clearly integration with Exchange (such as with MailTips: as you write an e-mail to someone, it’ll figure out that that person is actually on vacation and show you their status). Being a good Mac citizen… well, debatable. Could be worse, but could be better, particularly with things like text editing shortcuts (part of this is a deliberate design tradeoff for parity with Windows, but a toggle would be welcome).

@Sören I’m referring to latest Insider Fast build. If you are seeing the Not Google link, I think that means that you have the preview of the new version turned off. When it’s turned on, it specifically says that the account types I mentioned are “coming soon.” But I don’t expect them before it ships.

With accounts that are not Gmail or MS-hosted, you revert back to the old user interface (I use on-premice Exchange and IMAP so I’m out of luck).
The new search engine works well for basic searches, but completely lacks the advanced searches that you could still access when it was Spotlight-based. You still can’t reply in any other way than top-posting, no local rules, no scripts for rules either… Most of the advanced features were lost a while back when they tried to integrate some of the Windows code base and never returned :-(

Exchange support is great, but the shortcomings will prevent me from ever using it as my primary email client.

What a ridiculous waste of a title bar.

Also, "ready for Big Sur"? Did anyone at Microsoft actually pay attention to how sidebars work now?

Is there any email client that doesn't totally suck these days? I think I've tried them all, on both Mac and Windows. Too many of them are trying to be Email + Something Else. Others are missing basic features such as proper IMAP integration. It's like everyone has forgotten what email actually is.

The one I settled on is eM Client (paid version, on Windows) because everything on it works, the interface is passable (I'd prefer colored toolbar icons) and it has a great feature where the right-side panel can be configured to show the entire email history of the contact of the email you're currently viewing. e.g. when I get an invoice and click on it, I can immediately see all the other invoices sent from the same email address. I've never seen this in any other email program but now I use it all the time. It also attaches files as actual attachments instead of the inline mess that Apple Mail does.

@Ben G
Years ago I settled on Postbox (after Mail.app suddenly stopped seeing emails imported into its data folder). I like the hotkey Postbox has to bring up a little HUD to quickly sort messages from the keyboard.

The feature you mention in eM Client seems pretty neat; might check it out now that I'm on Windows as well.