Actually, older properties can get bundled with newer properties at a middle deal rather than everything being bought separately. It establishes a working relationship between both parties opening up the way for the cable end to get a solid deal on a newer property which can in turn be used to advertise the streaming side of the sellers on the cable side without having to buy commercial time. Cable time = streaming time if you play your cards right.
And as technically everything is online if you really look for it, that can't really be used as the be all to end all arguments against airing something cable side.