As to "The more time and energy you can give to your kids, the better off they will be.". That is very simplistic and like most things is more complicated than you first think. Children get used to being entertained, be it by a tablet or a parent. There is a downside to both, in that it is also good for a child to be able to entertain themselves and comfortable by themself. (Tablets & TVs aren't a child entertaining themselves.) From my personal experience, intensive parenting where attention is maximized on the child isn't healthy for either parent or child.
All this to say that simplistic takes tend to fall apart once they meet the complex variety of reality.