They just really like doing stuff, like all the time. That's their preference, being busy. If you like doing stuff all the time then you are inevitably going to get a lot done whilst also having a life you enjoy, as you like getting stuff done. I have noticed this from observation of highly efficient, effective people. They are not miserably filling their time with productive occupation because they feel they should. They actually like it. I read a book about growth mindset but the thing that struck me most was that the 'growth' mindset people have just found something they love and so are prepared to work really, really hard at it, even when its tough.
That's my problem. The things I like doing are not deemed productive. I like bumming around the kids and people I like, I like reading stuff I find interesting. I like watching bees in the garden. These are my preferences. I like bouts of busyness, but can't maintain it as a constant lifestyle choice like effective, efficient people can.
This realisation is actually quite freeing. Both me and highly effective and efficient people are living lives doing the things we prefer to do. We just prefer different stuff.