I think both stances need more nuance. Yeah - if your company doesn’t hire someone that can fulfill your essential duties while you’re gone, that’s on them.

But when you do have someone who can cover your duties while you’re gone, it makes sense that you can’t all take off the same day. I work in municipal government for a small city, and my boss and I are each other’s backups. We’ve worked together for years, and we haven’t taken the same day off yet, but both take several weeks a year. Heck - tomorrow there’s an annual conference we both should attend, and we alternate each year who goes because someone has to hold down the fort.