Without invoking religious woo? Sure, you selectively find pieces of evidence that vaguely fit your claims and ignore everything else.
How do you know what the inspiration was for a 10,000 year old cave painting? All we can do is guess, or find more cave paintings depicting the same event or object in relation to other known events or objects. We cant ever conclude "well, this looks like an astronaut to me, therefore astronauts of some kind visited this ancient culture", especially while someone else can say "not too fast there, because it may well depict someone in headdress"
Much like Nostradamus or arguably religion, it's interpretation of whats in front of you, rather than a solid testable theory - might well have been visited by aliens at any point in our history, but we sure haven't got any solid proof, just interpretations and ideas.
Now, this bit of your post may take me off topic, but here goes:
if you think about a lot of the ancient cultures…they do kind of sound less like Gods and more like real beings.
Two words: Jesus Christ.
Jesus Christ, as depicted by seemingly everyone who accepts his existence, was a human or more literally God incarnate. Jesus, even to Atheists, sounds more like a person than a deity. It's no real surprise to find human looking deities in human religion. Man was created in the image of God, so we've grown up with the idea of God being a vaguely human looking thing. The Gods and Goddesses of ancient Greece, of Rome, the Norse Gods, even the animal looking gods of ancient Egypt all have their roots with 'mere mortals' so to speak.
Even modern religions have anthropomorphic gods, or are at least how they are depicted. With the exception of the Flying Spaghetti Monster perhaps, but even he is described as having eyes and noodley appendages, as well as human behaviour.
So what does that mean for ancient astronauts? If we're looking for humanoid deities, we're probably looking for humanoid aliens too, despite having absolutely no evidence of whether deities or aliens exist at all, let alone what form they appear in. The theory is nothing but another idea that is taken by some to be fact without providing any concrete supporting evidence.
