I've only ever worked in the UK public sector (almost-a-civil-servant), at two places which were partly government funded, partly academic and partly a business. I've heard lots about this "proud to overwork" style culture but never seen much of it; not from most of my friends either.

Is this a cultural thing, i.e. we're not so proud about overworking ourselves in the UK?

Or is it because I'm outside of the tech bubble -- my work as a software engineer is mostly supporting science and research rather than pushing business products through the door before the next VC funding round?

Or is it just that we are generally more relaxed in an academic environment, where the salaries aren't so lucrative but we get appreciable amounts of time off?