Optimization is near and dear to my heart (see username), but I think it’s fine to call optimization processes AI because they are in the classical sense.
Back in the days when something like A* was invented, I' fairly sure it was called AI.
Now it's just another algorithm. So indeed, we don't call those 'AI" anymore. The bar has significantly shifted and does so each time a big advance is made.
Perhaps one day we'll understand what goes on in our brains to the same extent.