When "choice" effectively limits societal options or generates massive externalities and/or long-term unpredictable impacts, all parties upon whom the "choice" impacts are not given voice, or choice.
Often commonweal is a better guiding light than "choice".
It's the user's choice to use a cloud-hosted security system. They can weigh the trade-offs and risks for themselves, same as with any other system.
Whether that data is accessible by law enforcement is a completely separate issue. A proper solution would be limiting this access and requiring consent and transparency, not removing infrastructure options because you think you know better than everyone else about what's best for them.
The issue, by virtue of legally allowed warrantless access, is inextricably conjoined, and the impacts of that choice accrue to not only the decisionmaker, but to countless others. Your premises are false.
Your proposed (and grossly insufficient) remedy is one form of legal mandate.
I'd strongly commend Shoshana Zuboff, Hanna Arendt, and Paul Baran, amongst numerous others:
"On the Engineer's Responsibility in Protecting Privacy", Paul Baran, 1968:
Another view was expressed by AI pioneer and Nobel Laureate (economics) Herbert Simon:
"The privacy issue has been raised most insistently with respect to the creation and maintenance of longitudinal data files that assemble information about persons from a multitude of sources. Files of this kind would be highly valueable for many kinds of economic and social research, but they are bought at too high a price if they endanger human freedom or seriously enhance the opportunities of blackmailers. While such dangers should not be ignored, it should be noted that the lack of comprehensive data files has never been the limiting barrier to the suppression of human freedom. The Watergate criminals made extensive, if unskillful, use of electronics, but no computer played a role in their conspiracy. The Nazis operated with horrifying effectiveness and thoroughness without the benefits of any kind of mechanized data processing."
There is, of course, one slight problem with Simon's argument: The Nazis did make heavy use of mechanised data processing, provided and supported by IBM. Edwin Black documents this meticulously in his book IBM and the Holocaust:
That's a wildly unreasonable stretch and limiting freedom for the claim of security leads to far worse results.
Infrastructure and third-party vendors need to be managed against risk. This is no different than using Gmail vs your own hosted email box. Same with a million other services. Are you claiming that they should all be shutdown now?
Legal issues need to be fixed by legal solutions, not by disallowing the service from existing.
A legal mandate avoids the race-to-the-bottom trend.