Politics, sanitation, planetary orbits all affect me, and I contribute. But I don’t necessarily care about them all.
Your central thesis, that there “is no neutral”, is unworkable. Examples that fly in the face of it abound. Carve out the special cases, like you did for children, and there will be nothing left.
You claim you don't care; let's grant that for the moment, even though your energetic participation here suggests otherwise. Nobody's saying people can't not care. They are saying that taking a "not caring" stance while both benefiting from the status quo and contributing to the status quo is in effect supporting the status quo.
If you want to support the status quo, godspeed. There are many good things about it. I only object to people pretending the status quo has nothing to do with them when they quite obviously are an active part of it.
A newborn child takes no actions and makes no statements. It is utterly dependent, contributing nothing. Is that you?
It's perfectly reasonable to say that you are happy enough with the status quo to support it. It's also reasonable to be afraid enough of the status quo to refuse to be in visible opposition to it. What's unreasonable is to be a beneficiary of and contributor to an intricate system of economy and authority and then act like it has nothing to do with you.