I'm in a similar kids/work situation and it's going very rough at best. But then again I'm a completely terrible parent, barely capable as a normal functioning adult, and my kids inherited the coked up hummingbird trait from their mother.
So, no. I do NOT just work a half-day, I prioritize, I multi-task, and it's very difficult to maintain this lifestyle.
Serious question, why bother? Any normal job would have you working less (assuming it’s true that you never get a free weekend or holiday, which I kind of doubt). What do you get out of this? The ultimate satisfaction of helping a stranger receive email instead of being with your family on Christmas?
You may be an outlier who can do this, but the average human will break down with that schedule over the long term