Its mathematics and design beauty are powerful.
No doubt. But it's difficult to imagine a universe that would be orderly enough to permit life to develop, become intelligent, and contemplate the universe's beauty, and yet that same universe be so messy and chaotic that we would say, "Nope, definitely no design behind this, there's no way a god would be this sloppy." The two things go hand-in-hand, QC: The fact that the universe, for whatever reason, is so orderly, and the fact that we're here to observe it. For all we know, there were a trillion universes before this one that were chaotic, but even if they did support life, how would we know they existed? We have no proper basis for comparison to use as a basis for the statement "This universe is too well-designed to be accidental".
Also, what is beauty? How do we define and perceive it? Parts of the universe are in fact very chaotic and ugly. But when we want to feel good, we focus on the pretty parts instead. For instance, the beauty of an exotic bird, or a tiger. We don't focus on the manatee, the spider, the mosquito, the buzzard. We focus on pleasant activities like painting and music, not the unpleasant activities like suffering from disease and evacuating waste from our bodies. And yet you believe that all these things were created by the same God who created us in his image. Why don't we find everything to be beautiful, then? Surely not all of those things are the fault of Adam and Eve's Original Sin (which God inexplicably holds against us even though sins are not supposed to be held against the sinner's offspring in the Mosaic Law). I could go on, but you get the idea.
It could be that God is the reason the universe is so orderly, but if so, he's not the God of the Bible. Even when YHWH was angry and vengeful, at least he gave a damn about humans, whereas the designer of the universe, if he exists, must be much more detached from his creation. Anyway, the key point I'm trying to make it that we are well-suited to this universe because we need to be in order to thrive. As a part of that process of becoming accustomed to the universe, it's natural that we would focus on things that make us feel good, and that release dopamine in our brains. The alternative is to be afraid and depressed all the time. But we still have to acknowledge reality to some degree, or our actions will be ill-informed, and we'll just be deluding ourselves and confusing others who listen to us.