Public markets are a different animal all together.
There are some concerned there won’t be enough willing to invest. That is a real risk given people smell a bubble about to pop.
The other ironic risk is if the float is too small it creates an artificially high valuation by letting a thin, momentum-driven market price 100% of the cap table, which then collapses when lockups expire, supply floods in, and the real market discovers the stock is worth far less than the marginal buyers said it was.
For example there’s talk that in that scenario SpaceX could end up with a 5T valuation… for a company that did only $18.5B in revenue last year. Thats beyond irrational even under the most aggressive growth scenarios.