I saw an NYT piece about profits mattering again in Silicon Valley: https://www.nytimes.com/2019/10/08/technology/silicon-valley...

I don't quite agree that this is actually what the issue is lately. I think there have been two types of bubbles in the general startup ecosystem over the past few years that are not related to whether early stage startups are profitable:

1) One has been the under-estimating of unit economics in companies that interact with the real world (unlike pure software companies), which caused a lot of 'Uber-for-X' startups to go under, not to mention Uber itself struggling to maintain its hoped-for valuation.

2) The second aspect has been the influx of late-stage money into companies like Uber and WeWork, delaying IPOs, which has definitely caused some irrational exuberance in the sector.