I would tend to frown upon shrinking competition but in this case Edge wasn't really a player. The markets were already shared by the Chromium engine and Firefox. Chromium has the ancestry back to WebKit and KHTML so, to my knowledge, Safari also isn't a direct competitor. So, we're looking at a duopoly which naturally happens when things get complex enough and smaller players are left behind by the sheer lack of resourcing.
Browsers always were hubs of a number of technologies because loading markup language documents over network and rendering them onto screen with some dynamic programming abilities covers a lot of ground. While we sort of agree on the rendering, scripting, and styling of HTML5 by now this has just intensified with features like WebGL of WebAssembly which reach out to completely new domains. So, it's near impossible to compete in the scene unless you're a big, established player.
A modern browser is a lot more complex than operating systems these days and probably 10x more complex than old operating systems from the era where it was still possible for a small group of people to write a competely usable kernel and desktop in a relatively short time. In effect, the browser has become the operating system and to think, that's probably the very reason it's much easier to be a Linux or Apple user these days. As long as you can run Firefox or Chrome, 90% of your problems are solved. Even Windows is, for most people, just a platform to run your browser on. Then you use things like Google Docs or the web-implementation of Office to launch Word or Excel to do your work. But you don't need Windows to do that, and with a Chromium based browser that Microsoft must fully support for their web services you can just use any Chrome/Chromium based implementation.
In this light I'm amazed Microsoft would be giving power to Chrome and Google. Microsoft was and still is an operator in the operating system and platform space. How are they going to stay at all relevant if they just officially reposition Windows as a host for Chromium build? Surely things aren't as black and white but that's effectively how it is, giving up control. Microsoft can't reinvent themselves as the new Google because that's an uphill battle. They'd need to create a new space where they can thrive because operating systems don't matter that much anymore and the lock-in cash-cow that is Windows+Outlook+Office is gradually munched away by the web technologies.