My best guess would be that it either did too much or not enough. Getting an extra developer's worth of productivity from a tool is great but there could be other ways to make gains as noted in the shutdown page. Visual editing is a different way of programming and can be more or less productive depending on specifics. I recall doing some IBM DirectTalk voice/telephony app dev using a visual flow editor--it was the worst. There are of course success stories like the original Visual Basic 1.0. Xcode and autolayout is less productive but more expressive.
On the doing less side, are there tools for parsing/editing/outputting HTML+CSS rather than a full React integration? I've worked with designers that used Figma or Zeplin but we only tended to export the graphics and copy/paste the styles.