Fundamentally (and one would hope that this part is made clear to students, teachers, administrators and parents), what is being taught and learned is a method for developing procedures. And I don't mean "procedures" in the context of computation, but procedures in general. I'm talking about the act of dividing a task into its component bits, determining what has to happen in what order, and deciding when things are "done" (whether that's in the sense of being absolutely complete or "close enough for government work").
Those are skills almost everyone needs in life. Programming computers or computer-controlled machines is a great way to learn those skills because of their (to anthropomorphise a bit) literal-mindedness. They aren't going to make assumptions about your desires or correct your meaning. They'll do what you tell them to do if it's at all possible, even if what you told them to do is wrong or stupid, or fail in a most ungraceful way (unless you also taught them to fail gracefully).
We may never reach a point where we need everyone to be able to write software, but we're beyond the point already where we need everybody to be able to give and take instructions.
Many of us are taught music lessons early in life but only some become musicians. The main goal of these lessons is not really for us to become professional musicians in future, but to know that music is composed of notes, who the classical musicians were, what instrument are there, and so forth. The same thing applies to arts and painting classes. The basic goal is for us to get an idea about basic techniques and gifted people.
The main thing to learn is the fact that both music and painting are forms of expression and that we will continually encounter them in life. Also, with the help of these early lessons many uncover their inner genius and that helps them go in the known direction from that point on.
Since coding is an activity that trains one's computational thinking - a skill that is so relevant today - it better be introduced early in life too. It is also a form of expression, and knowing that it exists and how it can be applied is just as relevant as knowing about arithmetic, letters, music, art, etc.
I don't suggest that the format of the current classes is the right one (in fact, I believe that it is not), but it is essential to have a child-friendly methodology and teach coding, or rather "programming", as a skill early in life.
Similarly, programming is the ability to control computation. It's very hard for us to understand just how a society would behave when 90% of the population has the power to create any software tool it needs, to compute sophisticated statistics, and so on.
You'd be hard-pressed to find anyone today who disagrees it was a good thing that (almost) everyone learns how to read and write. I'm also convinced 100 years from now, you won't find anyone complaining about widespread programming ability.