That's a reasonable argument.

From the investor perspective, I wonder if that's good enough-- the people chasing unicorns and 500% IPO paydays would probably be angrier watching it become a low-margin but functionally useful company, than seeing it close up shop.

Over time, there's a lot of pressure on Uber's margins. The technology and business idea are obvious enough that the moat is pretty low. There's little reason for drivers to not be on every available platform, and you can do a splashy "Download our app to get $20 in credit" to growth-hack a new competitor. So you're always at the risk of someone launching a price war, and even if you can drive them out of the market, you'll have a hard time resetting customer expectations.