For context, my current job is in management consulting.
Unfortunately can't try it because I have client data on my work calendar. I read your privacy guarantee, but it's too big of a risk and too little of a reward to try. Risk: somehow my client data gets compromised and we lose millions of dollars in a data breech. (Might even be against some of our contracts to use.) Reward: I find out I have too many meetings?
Thinking this concept through: I use my calendar to do things like block off work time for myself, accept meetings I MIGHT go to depending on if I find them valuable, and to keep track of what other people are working on (e.g. they invite me but I don't attend). How does your analysis account for this?
Looking at the meeting stats you gave me: I'm not sure how this could actually help me change my behavior. A meeting is not necessarily a bad thing. Nor is a recurring meeting. Things like meetings not starting on time, however - now that's a problem. Also, some meetings are VERY important, but these results have no way to distinguish good from bad.
I can also already prevent people from scheduling on my calendar just by blocking off times I'm available. This is an Outlook feature.
Not saying THIS IS TERRIBLE ABANDON IDEA - just some things I think of when I look at this. As your idea stands, I personally feel low motivation to use it. Beyond "I spend a lot of time in meetings" or "I don't," there aren't many other categories.