> a large number are using third party app stores or installing APKs

Any source for this? I wasn't aware that third party stores are used by the general population as commonly as the play store anywhere.

I've been to a developing country where I suspect split between play store and bluetooth APK sharing is about 50/50. Most phones have APK sharing application installed at the point of purchase and some people aren't even signed-in on the Play store, despite using the internet and WhatsApp.

Xender is more popular than Play store near where I live

As commonly? Outside of China, not really a thing. But widely used, and complemented even more strongly with installation of APKs? Yes.

As an Indian who is around many non-tech oriented Android users, I am not sure about a large number of people using third-party stores. It will be interesting to see a survey or study about it.

Another thing is that with such bans, all major ISPs and network carriers are instructed to block the traffic to the related domains, so the app won't work anyway unless they roll out with a lot of changes.