I'm with most of the other commentators here - this is a confusing, expensive move for most. WIP (without enrolment) was a single, simple solution which plugged a big hole where employees used a personal windows device to access work information (just like Mobile Application Management for Android & iOS, but for Windows). And that was all that many, especially smaller, organisations wanted.
The alternative(s), as per this article, are a suite of 19 different things you need a doctorate in cybersecurity to get your head around, and many of them requiring very expensive additional licensing. I'm also failing to see an equivalent to WIP in there where you could apply a simple security layer around apps which contained corporate information. Now it is the information itself which needs to be protected.
The principles of the alternative solutions (which have been around for a while) are very simple, but the application of them is far more complex than your article would have us believe. And the impact on usability and governance more confusing still.
The key point? Not having a MAM for Windows is a huge blow - yes, the Purview solutions will provide better security, but they are so complex, expensive, and difficult to implement in reality, most small organisations will simply not bother which will leave them at far more risk.