I don't think it will ever be

Anyway found this great plugin:
https://srd.wordpress.org/plugins/wp-mail-smtp/

E.g. I have installed the WP Mail SMTP plugin, but SSL support with SMTP authentication didn't work on this specific web hosting.

Whereas the plugin Easy WP SMTP didn't work at all.

WP Mail SMTP usually is my go-to solution, but it seems this kind of functionality heavily depends on the hosting environment resp. web server software (Apache, nginx etc.), PHP version and the loaded modules.

Going to look into the Office 265 solution suggested earlier in this thread, but I'd prefer to not have to rely on yet another 3rd party service.

To insist WordPress uses PHP mail() because WordPress uses PHP mail() just isn't good enough.

No you read it wrong.

We are insisting WP uses php's mail() and that is sufficient because it is part of the standard default PHP build.

http://php.net/manual/en/function.mail.php

And since WP requires php 5.2.4+, and this is a standard part of PHP that some insane host would have to disable, means it's safe. Not perfect, but that's why we use it. Most, if not all, installs of PHP would have it.

To the user who finds a crazy host who doesn't? Vote with your feet. Take your money away from them. There are hundreds of webhosts who allow it, many as cheap as $3 a month.

but

unaware and underinformed users who desire an easy-to-use platform to launch an affordable website are prey to developers who do not know how to use it and use it unprofessionally.

To market WordPress as a ready-to-use platform for end users without proactively including this type of feature / enhancement is to ignore the responsibility to offer a robust and versatile solution to customers.

While the community is great at educating and contributing plugins that enhance the platform and inform new users, resistance to ideas like this are misguided.

As an improving developer already impressed by the vast range of built-in goodies the platform offers, I echo that SMTP Mail configuration (as well as other emerging standards) is a prime candidate for ongoing development of the product as a future-looking solution.

To insist WordPress uses PHP mail() because WordPress uses PHP mail() just isn't good enough.

In fact, it is a bright flashing light that we have a culture problem where the need of the end user is put on the backburner. That breeds complacency and irrelevance.

https://community.office365.com/en-us/f/148/t/237426

So again, this is a server config

Post: http://yourtechadvisors.com/2015/11/22/how-to-fix-the-1-email-error-in-wordpress/