You, as an employee, will be the one doing the firing of the abusive employer by refusing to be on call 24/7 for free. If you're actually valuable and it's act

You, as an employee, will be the one doing the firing of the abusive employer by refusing to be on call 24/7 for free. If you're actually valuable and it's actually required they will work out a deal with you to compensate you for it. They'll usually just deal without it, maybe with some abusive passive aggressive grumbling. If they're unreasonable, they will do you a favor and end the business relationship. If you constantly refuse to set boundaries with your employer because "if I do they'll fire me", you will reduce your effective hourly rate immensely. Don't do that. It makes them respect and value you way less, too, because you aren't valuing your own time - why should they if you don't?