So, how does Dawkins square his public persona with his lack of certitude? Easily. No matter how strongly Dawkins is associated with atheism, he is first and foremost a scientist. Therefore, "the existence of God is a scientific hypothesis like any other," he claims.
Similarly, astrophysicist Neil deGrasse Tyson claims the title "scientist" above all other "ists." And yet, Tyson says he is "constantly claimed by atheists." So where does Tyson stand? He tells Big Think: “Neil deGrasse, widely claimed by atheists, is actually an agnostic.”
To a certain extent they are correct, that as a scientist, which is how I look at the issue, it's best to say that there isn't yet any evidence that a god or gods exist but that in and of itself doesn't disprove the hypothesis. And really I don't have much of a problem with not moving beyond that and then declaring yourself an agnostic.
I do have a problem with part of Tyson's reasoning in the video within the link. I think for the most part it's about what I just explained. But he also goes into the societal implications of declaring yourself atheist and the problems it can cause when you're trying to have a conversation and educate people. He's right that it creates problems. But if that is what is keeping you from saying you don't believe in a god/gods, which is part of what being an atheist is, then I think it's kind of a cop out.
It's not like as a scientist you have to sit on the sideline until all of the evidence is in and a theory is either proven or disproven to the greatest extent possible. Though if you do want to take a side I wouldn't advocate holding that belief as strict dogma. Make a value judgement but be open to new data.
I say I'm an atheist because even though I wouldn't claim the theory of the existence of a god/gods isn't disproven, there is a lack of evidence to support it, and I don't think there is even a conceptual framework available to even attempt to gather the evidence. I think that's a more reasonable opinion than the theist one because they are making a positive claim about something existing while I'm making the opposite claim. As I said, lack of evidence doesn't disprove the claim. But because there is no evidence the atheist claim holds more merit.