I've run my own business for over 17 years. I get up early, work, stay up kind-of late, work, and get a lot of time in early on the weekends. It's not really that terrible. It's difficult, but doable, and I can still focus a lot of my energy on raising my kids.
I think that’s great, really. I also think that in your original comment you said that people should be focusing on what can be done with hard work rather than complaining about impossibility (paraphrasing).
Most people must work during daytime hours, and formal learning (for example, math that pushes the boundary of what you know) does not work very well for kids (or adults in my experience) in the evening. I’m glad that you have the flexibility such that you don’t have to do work 8-to-6, but that’s clearly not realistic or even possible for most people.
How does one hard work their way out of this? Start a business so you can teach during the daytime and in the meantime your kids do what exactly?