The phrase “general welfare” meant “as opposed to particular welfare.” I.e., Congress is not to make laws giving money or goodies to individuals.
Of course, “general welfare” was not intended to mean “whatever anybody thinks is a nice thing to do.”
Of course you are correct. Unfortunately that is not the viewpoint that prevails in our court system, or even among “our” representatives who, of course, had to take an oath to protect and defend the Constitution.