Believing that Brazil won't win the world cup is very different to simply not having a belief that Brazil will win the world cup. Please try not to confuse the two.
Let's run with this example for a moment.
Alice believes that Brazil will win the World Cup.
Bob believes that Brazil won't win the World Cup.
Charlie does not believe that Brazil will win the World Cup.
Is Bob's position the same as Charlie's? Is Charlie's belief incompatible with Alice's? Is Bob's belief incompatible with Alice's?
Answers: no, no and yes.
Let's say Bob believes that France will win the World Cup. Logically, then, Bob also believes that Brazil will not win the World Cup. Alice and Bob cannot both be correct simultaneously, so they hold opposing, incompatible beliefs.
Charlie doesn't really follow soccer, or he hasn't thought too hard about which team might win, or maybe he thinks that one of France or England or Brazil will win. Charlie does not hold the belief that Brazil will win the World Cup. But neither does he hold the belief that Brazil won't win the World Cup. Charlie's belief is compatible with Alice's. It is possible that Brazil will win the world Cup, in which case Charlie might say "Well, I didn't believe that would happen, but it was always a possibility". Charlies belief is also compatible with Bob's belief. If France wins, then Charlie might say "Well, I never said Brazil would win in the first place!"
In case this analogy is not clear enough for some, here Alice represents theism, Bob is hard atheism and Charlie is soft atheism.
Agnosticism is a different question all together. That's not about the belief per se, but about what a person will accept as reasonable grounds on which to hold the belief in the first place.
Alice believes that Brazil will win. That could be because she has solid reasons to believe that Brazil is a great team in good form, well prepared etc. Or it could be just because Alice so badly
wants Brazil to win that her faith leads removes all doubt from her point of view that the win will happen. The first situation, in the analogy, would make Alice an agnostic theist - the belief is supposedly based on evidence. The second situation would make Alice a gnostic theist, where the belief is held on faith, regardless of evidence.
Bob, like Alice, could be an agnostic atheist, holding the belief in Brazil's downfall on the basis of what he considers to be good evidence, or he could be a gnostic atheist, believing in Brazil's loss on the basis of faith that Brazil's team is no good (say).
Charlie is no different from Bob or Alice in this regard. He too could be either a gnostic or an agnostic atheist, according to his personal criteria for forming beliefs about who will win. If he does not share Alice's belief that Brazil will win because he doesn't think there's enough evidence to be confident in that outcome, then his soft atheism is agnostic. If he does not share Alice's belief because he holds a superstitious belief that South American teams will most likely fare badly at this World Cup, then his soft atheism is a gnostic one.
It appears that you are simply conflating increased enthusiasm with the removal of the word "agnostic". It doesn't work like that.
I think it does work like that, in practice, most of the time. Most theists are gnostic theists. They aren't usually too fussed with inconsequential matters like the amount of evidence there is for God. Such issues are secondary, or considered irrelevant. Just look at Jan if you want a fairly typical example of the type. Often, the degree of enthusiasm correlates more or less proportionally with the degree of gnosticism.
Agnostics are far more picky about matters of evidence, because to them the evidence matters. Their enthusiasm tends to correlate with the amount of evidence they see, rather than with the baseline strength of their predisposition to believe.
Calling oneself an agnostic atheist would make sense if persons who identify as such were not totally dumfounded when asked to explain what new activities and/or behaviours they might adopt if they ever dropped the "agnostic" title.
Dropping the "agnostic" title would mean adopting a visibly more faith-based approach to the belief and worrying less about the evidence for or against theism. You should have little trouble imagining the kinds of behaviours that would go along with such a change in outlook, but I can help if you need it.
It appears, at least as far as agnostic atheists are concerned, they are already acting on the deepest spectrum of atheism.
The deepest spectrum, if you want to use that terminology, would be strong atheism, as opposed to weak atheism. It wouldn't have any necessary relationship to the degree of agnosticism. Atheism is about belief. Agnosticism is about one's attitude to evidence.
If there is no meaningful behavioural distinction to pair to the doubt within agnosticism, their claim is sophistry .... sophistry because agnosticism is philosophical defensible whereas hard atheism is not.
Agnostic hard (or soft) atheism is defensible, as is agnostic theism. The positions that
I think are philosophically the most problematic are the gnostic atheisms and gnostic theism, because the gnostics have the problem of trying to defend
faith, while philosophy relies fundamentally on
reason.
The agnostic title becomes meaningless because you cannot explain it in relation to any behaviours of doubt.
The relevant behaviours seem obvious to me. The gnostic has very little doubt, because the gnostic has faith. The agnostic, on the other hand, demands evidence for belief.
