I would be more inclined to trust sources like https://transparencyreport.google.com/https/overview and Firefox Telemetry which come directly from the browsers. But even these do not count data from mobile apps (most of which have to be encrypted now I think), embedded applications, scripts, and APIs.
> from mobile apps (most of which have to be encrypted now I think)
Since the end of 2016 on iOS and since Android v9, apps have to communicate over HTTPS. I guess you can technically visit HTTP sites via a browser, but I'd bet that >90% of the traffic from smartphones is over HTTPS.
> We collect data from the browsers of site visitors to our exclusive on-demand network of analytics and social bookmarking products.
More details about their samples: https://netmarketshare.com/methodology
I would be more inclined to trust sources like https://transparencyreport.google.com/https/overview and Firefox Telemetry which come directly from the browsers. But even these do not count data from mobile apps (most of which have to be encrypted now I think), embedded applications, scripts, and APIs.