[seren]

I think you are on to something. If you are "savy" internet user, you probably hang a bit longer on the desktop than the average population because you are also a power user. If you are a "casual" internet user, mainly checking some social site status, etc, using a mobile is enough. Or to say otherwise, prosumer vs consumer. And it is more likely that you will use an adblocker if you belong to the first part of the population.

[ciaranm]

I'm one of a handful of people I know who still use a desktop on a (mostly) daily basis outside of work. They're all either devs or heavy PC gamers.

Having said that, I don't know a single person who doesn't at least use a laptop every other day or so. Most of my friends have smartphones, but I don't know anyone who relies on that as their only access point for online services.