The sites you mention (aside from Uber, which does not make a profit) found their way to profitability by building out and then cashing in from an apparatus of

The sites you mention (aside from Uber, which does not make a profit) found their way to profitability by building out and then cashing in from an apparatus of mass surveillance unparalleled in human experience. So if I'm critical about the "grow while burning money" strategy, it's because I've seen the damage the eventual successful business model does to civil society. It's a bait and switch that we don't have to continue falling for.