It all comes down to whether or not you think the question of Gold's existence is inherently knowable.
If you think that God probably does not exist and that there's no evidence for a sentient Supreme Being, but also that we'll never know for sure, then you are both an atheist and an agnostic.
If you believe that God does not exist, you are an agnostic. If you KNOW he doesn’t, you are an atheist. I’ve “met” plenty of atheists on the internet. I’ve never personally met an Atheist, but I’ve meat plenty who claim to be - at first.
It’s interesting that nobody was making the distinction you make until relatively recently. I think it is the “refining” of the message as holes are found in it.