Manager here. The right thing to do is to take yer PTO, don't work off the clock, and take your breaks without fail. My team is mostly remote, so hopefully this doesn't sound like it's coming from a place of privilege (but I think it applies to all workplaces) but it starts from management.
I take my breaks and I take my PTO and when I start and leave for the day I damn well make sure it's visible that I'm doing so. Part of it's self serving because yeah, I don't want to work more than I have to, but it's also to set the tone, as everyone else on the team knows they can/should do the same without any fear of reprisal or guilt from management.
I've worked in shitty places and I've worked for shitty managers who expected work to bleed into your real life (or, god forbid, be indistinguishable).
If your manager is “always on” then chances are they're going to expect the same from you. Fuck that shit. Life's too short. Hold your managers accountable when they don't take breaks, don't take vacation, or work off the clock because they're trying to “lead” you to do the same (either intentionally or unintentionally, doesn't matter.)