Is it really a widespread thing for people to get in trouble for not doing this
Yeah it is. Remember the whole “quiet quitting” bullshit panic? That was about people doing this and bosses (plus the pro-corporate billionaire-owned mainstream media) pretending that it was the death knell of businesses.
I’ve never answered an email or phone call while off work or on vacation and not once has anyone brought it up
Good. That’s exactly how it should be. If they’re not paying you for it, you’re not on call. That should be a given.
The only people I see doing this are the people that do it of their own free will
Unfortunately, that’s far from true. Lack of regulations. An obscene power imbalance stemming mainly from lack of unionization. A business culture that heavily encourages ruthless exploitation.
These conditions combine to make many if not most bosses abuse their workers in any and every way not specifically illegal and oftentimes even THAT doesn’t stop them.