There is (sometimes) a distinction between an IPO and cashing out. VCs may be able to sell some of their stake on the secondary market if they want to cash out. I think some Facebook investors and early employees did this actually.
Also worth noting that "no rush to IPO" is not the same as "never IPO". As a VC, you're investing with the understanding that an exit is many, many years away (if it ever comes at all), on the hope that this longer time horizon gives founders the flexibility to do crazy unicorn stuff. I can imagine a CEO telling the VCs "hey, we're going to wait an extra 5 years to IPO, but that's because we want to do crazy 10x return stuff that's difficult to pull off as a public company because of required SEC filings, activist shareholders, etc.".
Also worth noting that "no rush to IPO" is not the same as "never IPO". As a VC, you're investing with the understanding that an exit is many, many years away (if it ever comes at all), on the hope that this longer time horizon gives founders the flexibility to do crazy unicorn stuff. I can imagine a CEO telling the VCs "hey, we're going to wait an extra 5 years to IPO, but that's because we want to do crazy 10x return stuff that's difficult to pull off as a public company because of required SEC filings, activist shareholders, etc.".