Xiaomi phones support it in all regions. Think about it, a company famous for putting ads in system apps has the feature but "privacy conscious" Apple literally put in extra work to disable it everywhere it's not legally required.

That iOS toggle isn’t about privacy but about mobile data usage. Users with data caps can limit the usage for non-essential or high data volume apps (streaming or cloud storage apps come to mind).

I think the point is that the code path to deny network access for arbitrary apps exists (at least according to this comment):

> I also found out the Chinese version has the ability to block an app for accessing both mobile data and Wifi/WLAN data.

Yet Apple is choosing not to enable it for everyone. It seems like it would be an easy and obvious privacy win, no?

This is a strong indicator that Apple's privacy claims are little more than a virtue signal. Network sandboxing an app is arguably the strongest privacy protection measure possible.

Not really