I've got a three year old who is used to me working from home and doesn't cause any problems at all.
I also know of far more people who complain of being constantly interrupted by managers and noise in an open plan office. Its not like modern offices are an oasis of calm.
And yes, open offices are horrible this way too. That's why we're having this discussion about people wanting to work from home: for many, it's a lot better than the chaos at the open-plan office at work, even if it isn't ideal. For others, it's at least as bad (kids/wife), so they either deal with the office, or they go to a coffee shop or rent a coworking space or similar.
My daughters love it when I work from home, so they're very supportive of my boundaries.
What's the point of living in an ultra-expensive region if you work from home?
2. silicon valley is a nice place to live in.
There's a reason that coworking or small office spaces are so popular these days: for $500/month in many places, you get your own little office with a door that shuts where you can concentrate on your work, or a quiet cubicle among other people with similar situations. If everyone was able to make working at home work for them, these places would not exist.