You are confusing the old Edge that had an engine forked from IE and that MS exclusively maintained, with the new Edge that is a fork of Chromium. Maybe that the old Edge was not of stellar quality was simply because the age of the codebase of its engine.

I'm simply replying to the OP's assertion that "Edge seems like a blunder in general".

IE market share was declining before Edge was introduced, and it continued to decline after Edge was introduced. Since the browser engine switch their market share has actually increased a small amount! So all in all I don't think there's any evidence that Edge was a blunder.

Yeah, this does seem to line up more with the Windows8/Windows phone failure more than anything.

Despite people having a better opinion about Edge Chromium it didn't seem to stem the decline.

> death knell of Trident (the IE engine)

Nitpick, but the Edge name signaled the switch to the ground up rewrite Spartan engine. Trident is still sort of alive in its zombie corporate state in the Windows backwards compatibility swamp. Trident was still maintained for backward compatibility (and still exists in IE Mode in Chromium Edge), but Edge was always Spartan and it is Spartan that is dead (RIP).