why does having software updates mean giving up control of the device ?

Security Updates - They should be considered as in warranty servicing of faulty software.

Software Updates - These are turning out to be a scam in some ways. The decision to regularly introduce new APIs and forcefully obsolete old APIs/features is theirs. Consumers don't have to pay for it with the control. The cost of it should be baked into the initial purchase cost. A new feature that restricts access is an anti-feature.