For a while now I've viewed moores law as economically driven. There are generally advantages to having faster computers, but these computers have costs to develop. If there's a technological wall, funding starts going to it even before it's relevant in production chips. If a chipmaker stumbles onto an easy cheap advancement, it still pays to keep just ahead of their competitors, because they'll need money later for the next wall. Moores law is the result of economic pressure to go a bit faster hitting technological barriers. So it's exponential but choppy.

If an AI achieves dominance, Then it won't have competition forcing it to be more efficient, and it will only spend resources optimizing chips if that fits it's goals. (if there's a payoff in it's own internal economy of resources)

Maybe it will run for a hundred years on the chip designs available at the time of its creation, before it decides it needs to improve them.

Not Likely, but faster chips are not a human female in a torn dress.