These things you have heard were more true at the height of the .com boom. Short-term, a business can get a big push by throwing everything their employees have into their work. Long-term, people burn out or move on. Smart businesses have a strong emphasis on work-life balance. Keep in mind that some programmers really just love their job and want to take their work home and put in long hours, as well.
Rarely is coding an emergency, unless the business is not managed well. This isn't always true for a sysadmin. If the server goes down, the sysadmin need to get it up. If it is the production server, that's money being lost for your business. If it is an internal server, people can't get work done until it is fixed. Sysadmins rarely can work from home, but programmers usually can if they need to. On the teams I've worked on, it's not unusual for programmers with young children or bad commutes to WFH as much as once a week as needed.
If you love coding, keep doing it. Make sure you keep your skills up enough that you can always have your pick of jobs. When you interview, be choosy about work-life balance (if that matters to you at that point in your life) and don't be afraid to say, "I really don't like to routinely put in much more than 40 hours week after week. Once in a while, I'm happy to throw in everything I have for a weekend, but I don't want to spend all my evenings and weekends on work," if that's the case for you.
I find programming can actually be a very flexible, family-friendly job. I have 3 kids, two of whom were born less than a year after graduation from college (twins). I have great work-life balance, and even home-school my oldest children. I should mention that I am an SDET (I spend about 50% of my time on software development, 50% testing), but I think a programmer could do similarly well with their work-life balance. I do also think I want to someday do the "60 hours a week, just for fun" programming lifestyle, but that needs to wait until the other pieces of my life calm down.