Not really sure what you are saying here, it seems like you are a bit confused.
You were talking about phone numbers being used to access online services, and now you are posting links about the Indian governments Personal Identification number which is more akin to a National Insurance number in the UK or social security number in the US
> Do you think those folks in Asia and Africa sharing mobile devices have email accounts they can use instead?
Yes definitely. Huge numbers of people in these developing nmations share a single mobile device per family or household, yet they all have individual facebook and google accounts to communicate with the world. That is defintiely all controlled via email address, unless I have missed a feature of FAANG companies where you can sign up for accounts with a mobile phone number?
In India, it is exceptionally rare for any services (gov’t and commercial) to use email address. They use mobile.
One of many examples [https://web.umang.gov.in/landing/department/aadhaar.html]
That accounts for 1.3+ billion distinct accounts in 2023 right there.
[https://uidai.gov.in/en/about-uidai/unique-identification-au...]
Do you think those folks in Asia and Africa sharing mobile devices have email accounts they can use instead?