If it's "these start-ups suck" and "everything of value's already been invented" that sounds more like vague criticism of YCombinator -- that it isn't currently

If it's "these start-ups suck" and "everything of value's already been invented" that sounds more like vague criticism of YCombinator -- that it isn't currently producing the very high level of innovation people are hoping for -- than any given start-up. There could be any number of reasons for that. Perhaps there's a mismatch beteween public (techy) expectations of YCombinator and its current goals? eg, perhaps the public and press all expect start-ups to be totally original and adventurous but actually what gets investor funding might be a little more conservative following a predictable pattern. Or perhaps as YCombinator has grown and the process has become practiced, the focused impact it can have on individual start-ups is lower -- ie, there may be a little more "going through the process" and a little less "being put through the fire" than in the early days. Or perhaps it's just that as there's more coverage of tech innovation, people are now more likely to have heard of the idea before demo day (there's always other start-ups in similar spaces, but previously the public didn't know that). But all those possible reasons are speculation.