Which market has a bigger froth? Private or Public Equity?

Is it the private markets or the public markets that has a froth? Looks like it is the private markets. By a wide margin. Recent IPOs and their pricing & valuation as well as post IPO performance clearly demonstrates this. Take UBER's current hot IPO. From valuations of $120bn (and then $100bn), we have come down to $79bn and that is still above (for now) the valuation of $76bn implied by the latest private fundraising round. And UBER made it to that $76bn (or the dreamed up $120bn) from only $3.5bn back in 2013. It is still a growth story (albeit a slowing one with many issues) with over $11bn revenues but with a $3bn loss in 2018. Simple comparison with Facebook IPO back in 2012 demonstrates how farther we have come in the private markets. Latest Facebook private rounds implied a valuation of $76bn back in 2011. Facebook had a strong and growing global platform with 900 million users and a $1.8 profit before that $100bn public valuation (priced conservatively). Compared to the $3bn loss and 90 million users clustered mostly in a few American cities (24% of revenues in five cities) for UBER. It is clear that there is a lot of dry powder looking for exciting stories and nobody likes a 'down round' but seems like public markets has no problem with that!

UPDATE (05/10/2019)

As mentioned, public markets has no problem with a down round. UBER opening even lower than the 'low end of the IPO pricing' ended the day even lower with a 7.6% loss on its first day of trading. That takes the valuation of the company down to 70 billion from the latest private funding round of 76bn and this is a lot lower than the initially talked about IPO valuation of $120 billion. This has not been the trend for tech IPOs which on average increased over 20% on first day of trading. However it is a phenomenon that is being repeated with latest 'tech' IPOs pointing to the froth in the private capital markets.

https://www.bloomberg.com/news/articles/2019-05-09/uber-s-long-road-to-an-ipo-is-ending-at-a-less-than-ideal-moment