There is a bigger question we can use here to bring the TAG view home, and that is this; While it is true that everyone brings their own presupposition to the apologia game, and that fact is perfectly fine, the bigger question is, can the argument being made stand up on the presupposition being presented? OR does the presupposition require something else? Because if it can not stand up on it's own merit and authority, and or, requires something else inorder that it is true, then it is not true on it's own.
Do you see the issue?
If I say that logic, or reason, is my foundational starting point for the argument I am making (whatever that is) Then I have a problem if I am arguing for the non-existence of God, because logic and reason do not exist by themselves, as self authoritative, whereas God can. So, when it comes to the Teleological Argument, either philosophically or theologically, the foundation for the truth must begin and end with a self existing "thing" otherwise it must arise from something else that in turn must be self existing in order to support anything else.
Paul lays out this same argument in Romans 1 starting in verse 18.
You can argue the non-existence of God all you want from any presupposition you want, but if the argument you're making against the existence of God, does not prove the non-existence of God then your argument against the existence of God, fails right where it started.
That make sense?