LU now that I’m reading the question again I see it says: “tend not to be” so it allows for a minority who are in kolel and are not so ruchnius (is it used as an adjective?) So I take back what I said. I thought it referred to all people.
Yet we have different opinions about the dagrees of batole in kolels. That’s ok. I’ve no way to show I’m right, and I don’t think you have, so there is no point arguing.
It’s good to know you agree with my second point.