I’m not going to look for stats but as someone who’s been in the startup scene for a long time, it’s true and the stats are probably even worse than that. It’s totally inefficient for the entrepreneur but very efficient for the VC. One of my other observations is that the ones who do make it often come from families that have already made it and are able to leverage those connections and experiences.
This has not been my experience at all. I moved to the bay area in 2012 and 5 people I met living there have built unicorns/have net worth now around > $1BN. None of them leveraged family connections. this might be true in Europe but the best folks figure out how to move to america.