The demographic it's targeting is people who use GitHub for daily work professionally, not volunteer open source maintainers (just as the demographic Slack targ

The demographic it's targeting is people who use GitHub for daily work professionally, not volunteer open source maintainers (just as the demographic Slack targets is people who are paid to have Slack open 8 hours a day, not community chat rooms, and their product decisions make more sense in that context). But even volunteer open source maintainers are likely to find "On vacation until mm/dd" useful.