I'm frankly already appalled by how much data (proprietary data, customer data, employee data, etc) companies are fine leaking to 3rd parties, MS especially. Even if you assume that Microsoft could never ever possibly be hacked, or would never favor one of your competitors enough to hand them your data, Microsoft's MO has often been basically stealing other people's work/ideas and stomping out or absorbing the people they took it from. The data they get from outlook alone must be worth a fortune, but with everything the OS collects these days it's insane how little anyone cares.