You can say the same about Facebook and Google in China...You can sideload or use VPN. Some do. Most don't. Blocking FB & Google ecosystems allowed for China to grow their own competitors.
In the few Chinese that do pay for VPNs, most women use it to access Instagram for celebrities, most men for porn on Twitter.
Facebook was blocked by China in 2009. WeChat wasn't even started till 2011.
Facebook cannibalized social networks in the US and homegrown networks abroad. Though we'd never know, I'd believe they would have done the same in China.
[0] https://git.frostnerd.com/PublicAndroidApps/smokescreen / https://play.google.com/store/apps/details?id=com.frostnerd....
It's built into android.
Private DNS is available since Android 9 (or around 40% of over 2B+ devices).
Nebulo works with Android 5+ and Intra with Android 4+ (close to a 100% of all Androids out there).