[tmallen]

Or younger. 5'11", 155lb, and I mostly wear XLs. I think someone of my build but in their 40s would be more likely to ask for a L or even a M.

[menloparkbum]

Fashion trends are highly accelerated these days. 3 years ago it was gauche to wear XLs - the cool kids wore tight fitting size M t-shirts. Fitted t-shirts are now for washed-up 30-something web designers. Cool kids are back to size XL. I never thought I'd see the day when 1990s Theodore Huxtable / Dwayne Wayne outfits became cool again. Ugh.

However, since linux users are largely oblivious to the fashion world, I'm attributing this particular trend to weight gain.

[simulate]

Or older. Like most people, as Linux users age, they're likely getting fatter.