If you want to know about bootstrapping, then Thiel is not the guy to read. Zero to One is all about growth. And bootstrapping creates small businesses rather than startups (i.e. slower growth).
Slower growth does not necessarily imply smaller or less successful if you extend the time horizon beyond a few years. Data on this is probably hard to come by, but I'd guess also that this is especially true if you consider all the VC backed firms that simply die because they were not a raging success, and burned through all their cash.
