So how do we accommodate the following quote posted in the OP?
Posted by another member in another thread.
"Belief in gods is a commonly held position by most humans, but such beliefs, just like your (the) notion of self determinism, aren’t rational or consistent with scientific understanding."
I've just noticed but you have once again altered the quotation of another member. You have dishonestly inserted the "(the)" as if there is just one possible notion of self determinism, and that they consider this notion to be inconsistent with scientific understanding.
That is blatantly dishonest of you, and not the first time you have altered quotes in an effort to change their meaning. The issue the poster had was with certain notions - I.e. yours. Yes, there really are different notions, just as there are different notions of free will. You changing his quote is just another mark of dishonesty against your name.
Does every atheist believe as such or is this quote indicating a some what extreme view?
The quote indicates your extreme dishonesty. The actual unaltered quote merely indicates a disagreement with YOUR notion of self determination, the kind requiring what the poster considers a non-trivial notion of freedom, the kind he considers to be inconsistent with science.
Why is freewill and self determination associated with theism by an atheist, any way?
It's not, typically, unless one asserts that the freedom within the freewill and self-determination requires some spirit, some deity etc.
Otherwise it is just a disagreement as to the nature of the freedom that the deterministic universe allows. Some atheists think that the freedom is of a non-trivial kind, others don't, and think the only freedom to be found can also be found in a thermostat. How it is used, and the complexity of the system using it, may be different but that is the kind of freedom they see. No God necessary.
proxy God = "It means treating something non-Godlike as if it were God, I suppose."
by default = as a consequence of the deterministic universe being responsible for all human activity and decisions and choices. That Humans have absolutely no choice that they need to be responsible for.
so we end up with
"proxy God by default"
Your "proxy God" remains ill-defined. Do you regard the laws of the universe as a "proxy God"? Do you think humans are in any way able to do something that those laws say we can't?
I'll assume that for the last your answer is "no". Thus you think that we are entirely bound by those Laws, right?
So you believe in a proxy-God!
See how pointless this entire thread is yet?