I think Davedan hit the nail on the head as to the crux of the issue: how are we defining a god? Bring a person from da Vinci's time to our world, and he'd declare that we're either masters of high sorcery, or outright gods. Hell, even a person from a century ago would view our world as a sci-fi wonderland full of bright, amazing, impossible toys that nobody (except Tesla) could've ever dreamed would exist. What would be miracles to one group may be a simple matter of inherent understanding for the others. Take the internet for example: it allows us almost instantaneous communication across the entire planet with people we've never even heard of, much less seen. With it, almost any kind of information can be found, given enough time and patience. Its a great bazaar and Great Library all rolled into one absurdly powerful technological marvel that has expanded our capacity to understand as a species. Such things were the impossible fever dreams of science fiction authors when our grandparents were kids. Nowadays, the current generation is barely even cognizant of a world in which the internet doesn't exist, and can use it almost as easily as they can any other tool. What Shakespeare would've deemed sorcery of the highest caliber is a simple fact of life for us.
Basically, any so-called "gods" we could theoretically encounter may well just be a species so far advanced, technologically, that we are unable to comprehend their capabilities, leaving the admittedly careless to claim their works to be miracles or magic or what have you. They might appear all-powerful to the untrained eye, but much like the episode of Next Generation where Picard and the Enterprise crew become worshiped as gods by a primitive people, they could be no less mortal than the rest of us, its just that they've found more ways to extend life and cheat death than we have.
