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Here's the thing.
No, but also yes?
The way Ron is treated by his siblings is very specific. It's not like how they treat Percy where they all get annoyed by how pompous he is. Or the twins where they just roll their eyes and shrug their shoulders because what are you going to do? They're the twins.
Bill and Charlie seem like the most respectful, and my personal headcannon is that Ron is Charlie's favorite brother. Percy just acts the way he always does towards everyone else, the twins, Harry, Ginny, etc... So one could say his behaviour is quite normal. Up until OoTP that is, because we see how he genuinely worries about Ron's future in his letter, even if it is quite condescending and misguided, so I venture to say that the eldest siblings cared for Ron quite a lot.
Ginny and the twins is when things start to get complex. We don't see their treatment towards Ron become super aggressive or even downright bullying until Percy leaves, in his absence the twins find Ron to be their next target, notice how in GoF whenever Percy was not around it was Ron who they teased a lot more.
Then, Ron becomes a prefect, a couple of weeks after Percy, their own brother who was also the most recent prefect in the family, ditched them. Their association with prefects still relates to Percy, and this is not only for the twins and Ginny, but also for Ron himself. Ron is quite clearly scared to become the twins' new favorite punching bag (metaphorically).
And the reason he doesn't fight back is a big reason as to why Ginny acts the way she does. She sees the way the twins treat Ron, which is pretty harshly, and as to not be perceived like Percy, he does nothing to defend himself. Ginny sees that Ron becomes the punchline to every joke and decides to join in.
No matter, how you see it. Ron was in the right to be mad with Ginny in HBP for kissing Dean in a public place: she was in a place where she could've easily been found; she would've been a victim of gossiping, bullying and mockery; a professor could've caught them as well. Ron might've not used the words correctly, but he only tried to do what he thought was best for Ginny. She in turn virgin-shamed him, told him the girl he liked had already snogged the guy he was jealous of, and that he was pathetic. All in the span of a couple of seconds, and in front of his best friend.
Ron himself had been a victim of bullying throughout every single school year, wether it was because of his robes, his financial status, his quidditch skills. He knows how rough other students are, more than any of his siblings probably.
Ginny is very similar to the twins, she is very alike in the way she's assertive and has a mischievous vindictiveness to her (Zacharias Smith, Malfoy, etc...). She thinks it doesn't affect Ron, because they're only jokes, but sometimes those jokes are a bit too mean, and she doesn't care for it. She called Luna, who was her friend, Loony a nickname after her weird antics. She said Ron had a Pygmy Puff tattoo, because it was emasculating.
But she also cared about him, because at the end of the day they were siblings. They grew up together, but she was not the best sibling she could've or should've been.
Is Ginny a bad sibling to Ron?
I saw this discussion today on reddit and I want to know what others think.