I think yc would consider all those acquisitions you mentioned to be failures. One of the best things about yc is they are happy to get behind interesting projects built by interesting people and see what happens.
_I_ would consider all of those acquisitions to be failures, but YC has funded advertising companies and other "What if we sell user data?"-style companies in the past, so I'm not entirely sure. (Kuhcoon comes to mind, which was a notable backfire.)
