I hope they realise this as I questioned them about its legality so they might double check whats going on and why the root domain is 'banned' just on MTNL.
Ya I too suspect its a routing issue as my hops drops off as soon as it reaches their first DNS server. Whereas the traceroute for github.com proceeds through their servers to eventually connect with MSN network.
Edit: once again, can any other MTNL Mumbai please check if they are able to access github.io?
Also please mention if its FTTH connection or BB connection.
I tried it through my neighbor's FTTH connection and I cannot access github.io, so I am certain its not just my issue.
If someone else can check if they too can't access that would rule out that its just my exchange thats having the issue.