has had a dandy answer to ever problem that's shown up so far the moment the problem shows up
Has it? What was the solution to the IoM governmental situation? Are the Orks a hegemonizing swarm? If not, how do you deal with them? Do tangible souls change the nature of reality and upset the thought transferrence that is a regular facet of Culture existence? How can Chaos be ultimately defeated? Has the dissolution of the mind-reading prohibitions had any longer term affects on the society? Where are the Culture going to find reliable proxies?

There is no severe physical risk to the Culture. There are multiple situations with no clear right answers.

I certainly do not see a comedy here
Most interactions are fuelled by misunderstanding and farce. The ship names are overt gags. The reaction to the ultra serious "We're so scary" destroyer factions of the 40k verse has mostly been light hearted, with things like Necron pets and Tyranid pest control. And the po-faced religion of the Imperium being dismissed as just primitive mumbo-jumbo.

It's not an overt comedy. But it isn't really an overt anything, and certainly doesn't fit into a standard storytelling structure. It has comedic elements.