I got the point. I just disagree with the merit of the point.

Microsoft decided that additional complexity for the notepad application is worth the tradeoffs. I tend to agree with them: Notepad is traditionally most heavily used to peruse readme files, which today are primarily written in Markdown. Therefore, having Markdown support as a first-class feature makes good sense.

Furthermore, I point out that it is an optional application that can be uninstalled.