A few issues I have with the theory of 'Athens and Homer hated Ares because he's a patron God of Sparta'
Athens was home to one of the two notable Temples of Ares (the other is, and I promise I'm not making this up, Metropolis of Anatolia)
Spartans didn't heavily worship Ares, a tribe that they conquered called the Geronthrae did and they just didn't stop worshipping him after being colonized, the Spartans primarily worshipped Apollo and Athena (which probably explains why a bulk of myths about him are women running away from him).
While it is likely Athens didn't prop him up compared to Athena because he was a God that is a patron deity of Thrace (in myths at least, in real life however is a whole can of worms) because they saw the Thracians as barbarians and while the Iliad did him no favors, his 'violent, temperamental, and vicious' nature really isn't that much worse compared to most of the other primary Olympians and it's more than likely that Athens and Attica Greece didn't hate Ares, they were afraid of him because he is the literal father of horror, that I won't argue, they just preferred Athena in the day to day civic lives but when it's time for men to get to killing each other they prayed to Ares.
I really hope I'm mostly right about this otherwise I'm going to be bearing my ass again....













