Encarta is a great example of Microsoft winning a market, and after it was defeated, letting it fade out. Wikipedia in some ways beat it, but the interactivity elements of Encarta make it something that you kind of wish had a more direct role in the modern day.
I wrote about this topic a few years ago (https://tedium.co/2017/07/13/who-killed-the-encyclopedia/), and it led a former CEO of Encyclopaedia Britannica to speak up (I added some of his comments to the piece). There was a lot of back-room wheeling and dealing around digital encyclopedias during that era, much of it centered around Encarta—Microsoft acquired a lot of publishers during that period and it effectively disrupted most of the rest out of existence.
But even considering that, Encarta was special. I think Microsoft had the right idea—it was the killer app for CD-ROMs—though it turned out that the internet would only make it a temporary success story.
It didn’t have to be like that, honestly. Imagine what might have happened if, for example, Microsoft worked more closely with the Wikimedia Foundation on the highly visual treatments the company was known for with Encarta. The nonprofit ownership was a good move, but the fact that MS seemed to cede the market entirely, especially so soon after disrupting the whole thing, was unfortunate.