Whereas with gold, it isn't there in the rocks - not in the same amounts. No future chemical wizardry is going to make it extractable, because it isn't there to extract.
To make gold more abundant is going to take transmutation, which is a much bigger ask.
Now, if you want to say that the ancients didn't know that aluminum was there and gold wasn't, and therefore lucked out by picking the one that wasn't there, I would agree with that.