Unless you run a business that literally requires 24/7 connectivity, it's healthy and fine to step away. If your employer won't respect your time with your family, they don't respect you.
It's up to you to decide if you can live with that. I could not.
Why do you assume that OP's employed? And if they are, why do you assume that they can afford to just walk away?
For the second, I get it. Not everyone can. I shouldn't have when I did, but it worked out okay for me after a few months of pain. And I'd do it again in a heartbeat. We had to downsize our lives and I switched to a field I never thought I'd work in. Turns out I love it, and have way more time for my family, even if we can't do massive vacations now.
But I also agree with parent OPs sentiment - going offline, putting your phone away really connects you back to real world and family. This has been studied ad nauseam. Same as food, substance or any indulgent abuse - it's up to you to control yourself.