"... anything not necessary for survival on Earth is superfluous, and may well get in the way of our using what we do need."
I couldn't disagree with you more.
To begin with, anything we don't know CAN hurt us". There is no such thing as "superfluous knowledge".
Once our immediate survival needs are met, learning "useless" things is the only point of living. Not only might they someday turn out to be vital, but they are fun. The whole purpose of human existence is to avoid pain and have fun, and I can't think of anything that's more fun than learning new things, making pretty things, and sharing them with the people we love.