I wouldn't say that completely, they do have other products that people seem to love. Yahoo mail is still very popular. Yahoo finance is still very popular also. They do have a bunch products they bought that they never seemed to be able to use properly (delicious, the now sold zimbra...) I really think they should have ignored search a few years ago and continued developing products like Flick, delicious, zimbra and other cloud services. They had the engineering talent for it.
Maybe I'm way off but I still think they did do good ideas that they never fully developed.