We're still in a boom period, where many start-ups/VCs are operating with deep pocket books and instructions to scale fast at any cost. During the next bust, lean will come back in fashion.
I think it would take a very severe recession, in the 2009-2010 style, to hammer venture capital down considerably. Instead I expect Japan stagnation to continue to envelop the US economy, and for the exact same debt-laden reason. Ever slower growth, low traditional inflation (higher real inflation from currency debasement QE), debt taking up an ever larger share of capital available for investment, stagnant productivity, stagnant wages. With the enormous amount of wealth in the US, trillions of dollars will always be looking at the venture capital market in a given decade. ~2012-2035 will probably be the best years for venture capital in US tech history, and broadly the best context for start-ups, that we'll ever see. It's early in the loose money sloshing period from perma low rates, but not yet late such that you're eating an always-on QE real-value debasement hammer constantly (which sucks down your real value creation, as you run uphill against the Fed while it tries to debase government debt to keep the US Govt solvent).