This is how it works where we are. In our onboarding, HR showed us a tutorial of how to apply for leave, using her own account. "Oh see I took a month off this year, and it's okay if you need to take time off for yourself." My manager was also on leave then - he left a welcome message saying to contact X for GitHub access, even though it would be fast for him to do it now.

That's quite impactful when you're given the message that early, that the people in charge of rejecting your time off encourage you to do it.

There's also something on the wiki warning us about burnout. There's plenty of talks on avoiding burnout. Nobody attends them, but we get the message that it's costly to the company when it happens and not something to be proud of.