Not if a large fraction of their traffic is mobile.

I expect everyone on the site to own a real computer too. I interpret the question as "people that use X as their desktop OS" because of the context.

To note: I wrote "~80%" because I was too lazy to look up current statistics and accepted the parent comment at face value, while also allowing a slushy figure. The general presupposition of my comment remains the same regardless: it's unwise to assume that the desktop computer market reflects a website's visitor segmentation.