My Chinese phone (iPhone 6s) had a similar flaw. Okay, that was tongue in cheek, but I don't see how adding the China qualifier adds anything new or interesting other than inject bias.
I should probably have said "cheap phones" - I am not sure. Every ODM/OEM is different.
But it is an interesting discussion for sure and made me think about my experiences. What kind of software engineering department would make a mistake like this? I bet 1 USD that I could spend one hour with their engineers and I would be able to predict if this would be a mistake they would make. :)