Atheists & Agnostics

Sorry, you are stating that for you, all propositions are either yes or no. You can believe that if you want, but the fact is that there are non binary propositions.

In this case, the agnostic is simply saying that they do not have enough or any information on which to make a decision. They don't know. An atheist or a theist may feel that they have enough evidence to be able to answer your binary proposition. Good for them.

The agnostic just does not know.

I have listened to this discussion for decades. It is common for both atheists and theists to argue that there are no agnostics, because they assume this is a binary proposition. It's not.

Some people just don't know. They are agnostics.