Yes, Edge has improved its support for HTML-features. Here IE11, Edge 12, Edge 18 (current), Firefox 60 and Chrome 68:
https://html5test.com/compare/browser/ie-11/edge-12/edge-18/firefox-60/chrome-68.htmlEdge has also gone from supporting only the same proprietary audio and video formats supported by IE. Now Edge has full support for WebM and Ogg, ranging from the obsolete video compression format Theora to the brand new AV1 (for the latter, an optional install (beta) is currently required).
But as I am sure you have seen as a long time user of Presto, support does not guarantee compatibility. A browser may do everything right, but some pages still don’t render rightly.
Being limited to Windows 10 makes it hard for any web developer not using that system to see the page in Edge. Since Chromium is a multi-platform browser, so can Edge be, beginning with other versions of Windows (7, 8.1), and then Mac OS, and possibly others (Linux-based).