Shouldn't this be business 101? Plan for a downturn, use your resources wisely to avoid future disasters? Even after several market crashes, it's surprising to see so many businesses acting so recklessly with their capital. You would think being in the valley they would know better.
It depends on the market conditions. VC funded startups are not a place where I think that really makes any sense. Most billion dollar startups haven't even been through an entire business cycle.
The VC market is not looking for consistent year over year 8% growth for the next 40 years. If they wanted that they would have bought index funds and told startups to fuck off.
But, regardless of frothy times or not, the advice is solid. Keep your burn low. Run as lean as possible until you've figured out the business model.