From a technical point of view, I've also been puzzled by the "support for" update descriptions. (I don't want this to be judgment on either Civ 6 or AMD.) Surely the game developer has been running for a while, testing, providing feedback when necessary, perhaps getting non-public releases to test. Do new games use the API in such a different way? If it's optimizing the engine, might it break other things? If it's game specific optimization, instead of baking it into the driver, shouldn't it be data-driven via a game developer supplied config? (I realize that's not easy. I'm a software architect, I've maintained APIs before, doing it right is really hard.) From a high level system and process point of view, the extra effort of getting Civ6 to run well should be placed on those that want to run it. I just want my video editing to work well, so I don't want to download a new driver to hard code improvements just for Civ6.
A fair answer would be that "support for Civ6" means fixing a bug or performance issue that no one else has run in to before, and most people don't want to hear the detailed answer.. but that still leaves the question why it wasn't already fixed in the driver when Civ6 was being developed and tested.
As a specific item, if it's an SLI profile, it seems to me as an engineer that the sli profile should come with the game and not require a new driver. If it's coming from AMD, then millions of people who never run Civ6 are downloading and installing data specific to it. That seems sub-optimal.