Unless their statements regarding the design of these systems are blatantly false, or they are forced to add data collectors on purpose to target individuals, t

Unless their statements regarding the design of these systems are blatantly false, or they are forced to add data collectors on purpose to target individuals, the answer is close to nothing. You can opt into full E2E encryption [1] which makes it nothing, presumably at the cost of some convenience features. [1] https://support.apple.com/en-us/108756 https://support.apple.com/en-us/108756