"No, you need to take the dog out - I am working"
"Ill just watch thi one segment of 'X'"
"Just a short nap to clear my mind"
There are far too many temptations to do other things at home - Each child is a 10x multiplier.
I don't have to commute, so I save money, get to have breakfast and lunch with my wife and kids (and help out), and after work I have time to cook us a healthy meal from scratch (I actually enjoy cooking too).
I have a fiber internet connection, so no issues on that front.
I honestly have far more distractions on the 1 day a week I go into the office (which is open plan and includes a co-worker who does little but chat all day...).
As someone who now manages a remote team, it can be tricky to help people adjust to working from home. Some people just have to have that physical partition because they or their family won't adapt. I recommend a co-working space for those people; that partition can be essential for keeping them productive and happy.
The other side of this coin is making sure you set that time aside for your family and personal recovery. If you had a coworker who never left the office, you should worry about ingrowth and their health. The same is true for a remote worker who seems to be always online and always working.
Personally even when working remote, I need to go to a cafe... I like being around people but none of them can interrupt me, no TV or couch or bed or fridge or pet or yard or porch in nice weather to distract me.
But I've worked with people who have been WFHing for decades. I envy their ability to do so.
You wouldn't be doing those things for your kids if you were at remote work (because it would be physically impossible as you'd be elsewhere). So why do them when working from home? Just because you can? No, close the office door and/or set clear boundaries.
The difference -- and the great benefit -- with working from home is that for the far fewer things that DO matter, you will be there for your children.
The meetings, the chats, the endless browsing