I never thought I would say that Windows lacks apps. This is however, how I feel after using Windows 10 for a few day.
Granted, I am not a heavy Windows user and my experience is mostly confined to the PC that was handed to me at work. However, I suspect that for the majority of people, this is actually the full extent of their Windows experience. Although I am not a heavy user, I am pretty much an average user.
Now if your knowledge of apps on Windows is mostly limited to Microsoft Office and Exchange, then the only experience with a huge app ecosystem would be the iOS App Store and the Google Play store. You would not have known that there were a ton of apps for Windows even in the old days, and even if you did, you would not know where to find them. You best bet would have been to go the your local retail store to get a shrink-wrapped version, and no, Amazon isn’t really an option because they don’t even bother to include the descriptions that you can find on the boxes.
Therefore I would argue that for a regular user, their perception of the app ecosystem for that OS depends on the default app store, regardless of how many shrink-wrapped apps you can find at stores. In this regard, Windows 10 falls short. Terribly short.
It would be much better if Microsoft had a store for their non-Metro apps, much in the same way as Apple has their Mac App Store. They could even simply provide an app or a link to the Microsoft Store (which for some reason is down today) where they showcase hardware and software that run on Windows.
On the other hand, my expectation is that developers that are quick to embrace the Windows Store might get a lot of exposure, just like how early iOS developers were able to earn more money more easily than the current ones can. The Windows Store was available since Windows 8, but since the experience of using Metro apps on desktop PCs was so bad, I expect the vast majority of users didn’t take a serious look into the Windows Store. Now with Windows 10, the situation should be very different.