Extremely naive view. China is a totalitarian state that can compel its companies to hand over all private data if asked. In your rosy "presumption of innocence" scenario, by the time they're proven guilty it's too late.
This is preemptive measure that is a prelude to greater 'decoupling' from China. If a hot war breaks out, you don't want the country dubbed the number one strategic threat having access to 25% of citizens phones.