I'm not sure he's a visionary. He's more into going with the flow, mimicking successful competitors. Amazon went big with AWS? Let's try to do the same! Google and FB are tracking everybody? We can do it, too! Apple is pushing updates on their mobile devices? We can do it on our desktops but in a way that makes everyone mad! All phone manufacturers add fluff to their devices? We can bundle adware, too! People love Linux? Let's add it to to Windows! They also like open source? Well, we can't buy that, but we can buy GitHub!

The list could go on but the point I doubt Nadella is a visionary, he's just following others. Not necessarily a bad thing for the company and its shareholders, it's a fairly safe approach. I miss the days when they actually had original ideas, like the Kinect.