Not completely wrong - except the bit about blandness. If I want bland characters and dialogue I'll just crack open Three Body Problem again.
Seriously though: Matter, Surface Detail, and Look to Windward are all fairly clear counterexamples to your template.
The first involves an explicit refusal by various advanced civs (including the Culture) to help a deposed leader of one such primitive society to reclaim his throne. The last one deals explicitly and at length with various Culture citizens reckoning with its actions both recent and long past, and the consequences thereof.
Meanwhile, Three Body Problem is an impressive series with interesting ideas which nonetheless left me unmoved. I didn't care about any of the characters, and as someone pointed out elsewhere, the dialogue is not great, which to be fair could just be an issue of translation.