If the US had solid proof of any actual violations, why didn’t they just sanction Huawei like it did ZTE?
Going after an individual instead of the company, especially close family to the owner, smacks of mafia style scare tactics and fishing expeditions where the US is trying to find dirt rather than because they had any real proof.
It could also ironically be classed as precisely the kind of corporate espionage the US accuse China of, as she was likely to have sensitive company files on her person at the time of her detection, which would no doubt have also been seized and copied.
Sanctioning Huawei, China's largest telecom company, is bound to invite retaliatory measures and heavily detracts from the US narrative that a thaw is in order for Sino-US trade relations. Arresting an individual while overtly leaving Huawei alone allows the US to take punitive measures without compromising its promise to end the China-US trade war. However, I am almost certain that the US would have the justification and means to sanction Huawei if she really wished to do so.