I'd say this is defiantly unethical yet I feel like this can actually be considered a good thing to exist: the web being monopolized by just one major browser/engine (which is Chrome/Blink/WebKit nowadays) is obviously a problem so anything than can increase presence of alternative browsers/engines can be considered a contribution to the web ecosystem diversity (although, honestly, I wouldn't recommend any of my friends/clients to use a Microsoft-made browser as these have a strong history of being far behind the web standards progress and exposing system vulnerabilities via ActiveX).
Also, IE before version 6 had a history of being extremely innovative (DHTML, anyone?). That's part of how they won the first browser wars (that and pushing the browser through their OS).
> and exposing system vulnerabilities via ActiveX
Now that's just baseless fearmongering. Edge supports neither ActiveX nor Java Applets. That's why IE is still around: for legacy websites in corporate intranets that still require this junk. I'm not sure if IE is installed on non-Enterprise SKUs of Windows 10, but it would surprise me if it was.
