Sufficient for what? Explaining why we are here and what is our purpose? No, it’s not enough.

God will always be there if they seek him. Pointing out we live in a fallen world is not a “gotcha” for the existence of God. Neither is the existence of evil, if anything evil is proof God exists.

Because they understand that we have to accept one of 2 things. Either there is an eternal something (universe) or an eternal someone (God). Once you come to the conclusion that the evidence points to a creator then the natural next step is to figure out who is this creator. No offense, but agnosticism requires a form of intellectual laziness or lack of curiosity imo. I was agnostic for many years after growing up Catholic for what is worth.

Intelligent people want answers. Answers can be found.