Microsoft gets control of a segment and then does not change anything. It makes things require more power, generally larger, and it provides a means to support newer versions of existing technology. Very little new stuff happens in each release of Windows or Office. There are new skins and things get moved around but it remains fundamentally the same OS.

What I guess you probably want to argue is that Apple doesn't invent anything, which is not entirely true but lets give it the benefit of this argument. Apple still adds features to things and changes. In fact it does so at a rate that often irritates people.

In no particular order, the touch mouse, the app store, haptic feedback, the mac pro using only external expansion, hand off, micro sims, unswappable batteries, health kit, facetime, BLE support in phones, fingerprint security, RFID etc. Yes, Apple invented only a few of these things, but they do keep implementing them and pushing them out. They are not content with dominating a market and then bloating.

For example, the new Macbook has one port and that irritates people. Apple is pushing them toward new ways of working on they don't like it. It also has haptic feedback and force clicking. The watch of course, is coming up. Who knows if it will succeed? It's certainly not the first smart watch. But that is a sign of a company trying new things.

Google does this also, almost always before Apple although with somewhat less focus. Its core remains search and data but it does experiment with new technologies. Glass, Project ARA, Project Tango, etc. Google had Wallet long before Apple did ApplePay, but the financial industry support was poor because of Android's open nature.