You mistake "lack of knowledge" with "confuse".
We humans lack the answers of the most of the universe and what happened before big bang and what made it happen etc.
So an agnostic when asked about these questions would simply say "i dont know" which to me seems sensible rather than make up answers like theists for only to be debunked by atheists.
In a way, Yes. However you missed my statement here, :Agnosticism is a scientific thought.
Agnostic belief that relates with doubt("I don't know") is just one part of it. There is another belief where the person who calls himself agnostic accepts the fact that a God exists, but he does not believe in the human interpretation of God, also called deism or even agnostic theism with slight variance between them.
Also, something all agnostics should know. The moment you call yourself agnostic, you also become atheist. This is because all thought of atheism and agnosticism are quite interrelated. "Lack of knowledge" is actually a form of negative atheism while the one what you assumed to be atheism is actually positive atheism.
In general terms, agnostic believers are actually between atheists and theists. So, the victor of the debate is where the agnostic will fall under. That's why it is the "I am confused" group and "I am waiting for one of you to win" group.
"Lack of knowledge" is actually negative atheism. Agnosticism that talks about "Lack of knowledge" is divided into two groups, one which believe God exists but cannot be verified is agnostic theism. The one which does not believe in the existence of God and that there is no way to verify it as of now called agnostic atheism. There is very little difference between agnostic atheism and negative atheism.
One argument theists make is that in case they are right, then all the atheists will supposedly burn in undesirable places in the Universe. In case they are wrong, then their life will continue as usual. So, by that logic atheists are in a tougher spot. So, there is one more joke about agnosticism, "It's better to be safe than sorrrry."
Atheism,Theism and Agnosticism are strictly belief systems where the arrogance of the Atheist is supreme. This won't change anytime soon.
There is probably a "I don't give a Fk" group under atheism as well.