Earlier quoted context omitted.
Edge is a chrome skin. They don't have engineers working on a browser, they have engineers working on a _theme_.
1. It doesn't really matter. Most users don't even know what a browser engine is much less care, so whether it's a fully independent browser or not is irrelevant to their adoption in the marketplace. 2. The story was no different even when they were still using Trident as their engine.
When 85% of people use the same browser stack we're back in the bad old days of IE6.