I'm in general agreement, but I'd nuance it by saying that you need to take into account the underlying enthusiasm of the person. If there's something I need to get good at for my job but I find it very boring, then that's going to take a quite a bit of discipline. However, there are some other things in my life that I've had to extert almost not discipline to learn (and, IMNSHO get very good at) because I have an innate enjoyment of the subject.
I guess what you said needs to be said. It’s not really play if you make someone do it. For my son, a lot of it is redirecting and guiding the things he is already trying to do. (For example, my toddler takes his clothes off, so my wife and I would then have him put it in the laundry basket. He thinks it is fun).
As far as discipline goes, the value is being able to generate it from within. It’s a long grind, and it is not always fun.
