Homeless woman charges at him, he probably had less than a second or two to react and did what he’s trained to do. Front kick to the body to keep her away and defend himself. If it was a homeless dude tweaked nobody would have a problem.
In that regard, I see no problem with what he did, he had every right to defend himself especially since he was probably startled and had no time to assess the situation.
that being said, it was pretty douchey to brag about it and call her it. Given the sensitivity of the situation, he definitely could have handled it better and explained his perspective on being startled and feeling the need to protect himself and his dog and whatnot instead of bragging about how much damage his kick did