Microsoft announced earlier this year that it would remove applications from the Windows Store that do not comply with the age rating policies the company had adopted. The age rating policy is based on appropriate age and content ratings administered by the International Age Ratings Coalition (IARC) rating system. Microsoft said these ratings are about the suitability of the content in the app, rather than the age of the target audience for your app.
Well, it meant what it said. A large number of applications have been removed from the Windows Store, with reports ranging from 90,000 apps and games to more than 100,000. Given the Windows Store has (or had) 329,000 apps, that's about one-third of the total apps.
The 100,000 number is actually low. One report out of Germany puts the number at 174,203, which would be half of the apps.
The apps aren't gone, per se, they are just not visible to users anymore. If the developer submits age ratings for their app, they will be relisted. All the developers have to do is to access the Dev Center and fill in the age rating for each of their apps and/or games.
Microsoft had set a deadline of Sept. 30 for developers to comply with this new requirement. Obviously a lot of developers did not. There are basically two reasons for not responding: one, the developer was sloppy or didn't take Microsoft seriously, and two, the developer has abandoned the app and didn't care. There's no indication of the ratio between the two.
Word is mostly small and lesser-known applications have been affected for the most part. Major name apps are still there. But it's still quite a culling.