You can't even disable it completely, at best in e.g. Lightroom you can pause the cloud sync and it may get re-enabled without your consent. You will only notice that your upload bandwidth is suddenly saturated and if you have a monitoring tool installed, are you able to determine who is the culprit. It once chewed through my meager monthly quota overnight when I installed it on a laptop prior to going to a friend's house who didn't have internet while tethered to my phone. I was very unhappy about that "feature" to say the least.