Earlier quoted context omitted.
GitLab Just (partially) sold. However: If they don't want to (fully) sell basing the price on a value someone else might eventually pay for a (full) acquisition doesn't make much sense. (Unless you assume they revise the decision, but then the argument about not selling is moot again)
Look at Facebook. Zuck has no interest in giving up full control to someone else, but he does want to be a public company.
The argument Here was "ORCL, MSFT, SalesForce and a few others would pay 10B+" but those would pay those valuations only for full control.
FB's market cap is around 900B$. Gaining full control over FB would be valued a lot more.