I have 2 remarkes:
- that's from 2016
- that seems to be worldwide (I see for example swiss and french providers in the list), which isn't necessarily relevant. Gmail can be a monopoly in the US for example, while not being one worldwide.
Unfortunately I cannot find better numbers, if someone does that would be interesting to discuss.
A bunch of people have listed Gmail on their lists, but Gmail is not even close to a monopoly, even in consumer email. https://email-verify.my-addr.com/list-of-most-popular-email-...