I see no evidence for any of the points you are trying to make either.
You seem to equate revenue with success, which is not how this stuff works. Shareholder value is actually tied to the prospects for long term success (accumulated profits over time). MS shares were considered overvalued, not undervalued when Ballmer left (or depending on your interpretation, fired by an unhappy board).
Its OSS contributions are critical to both MS and how well it is able to convince developers to build on top of MS platforms. It's critical for it's credibility with Azure. I know people that now consider this a serious alternative to AWS or Google cloud that for sure don't have any interest on running C# on Windows Server while using SQL server. But it sure is a nice way to run some Linux stuff these days.
Satya Nadella also had to absorb a lot of the Ballmer era mistakes. Like paying five billion for the right to shut down an organization (Nokia's Phone business) for probably billions more. As I recall, that was one quarter where MS indeed made a historically unique loss and Ballmer pushed that deal through. Bing indeed is another dud. Windows Phone itself of course was the latest in a series of failures for MS to capture the mobile market that date back to last century.
The fact that it took a few years to recover after Ballmer left strongly suggests that 1) there were indeed problems in MS (i.e. shareholders were right) 2) Nadella addressed those problems. MS is of course valued around a 1 Trillion or so now. This may have a thing or two to do with the fact that he's not doing that bad of a job and that their future looks a lot brighter than a few years ago.