Yes - one of the later novels does mention that other advanced societies do regard the Culture as being a bit immature in their insistence that they won't subli

Yes - one of the later novels does mention that other advanced societies do regard the Culture as being a bit immature in their insistence that they won't sublime. Incidentally, Subliming reminds me a bit of the transition from the Beyond to the Transcend in Vinge's Zones of Thought stories.