Blockbuster has nothing to do with this. That was a failure in the traditional sense. I never argued that somebody is "too big to fail". The parent poster argued that if Dropbox failed, it would not be a big homerun. What I argued is that even if Dropbox valuation failed by say, 90% and it got sold, it would still net around 500MM. That would be a failure for the latest investors, but definitely still a heck of a success for YC (I am disregarding purposedly here liquidation preferences, etc, but you get the idea)