Someone who harms someone as a consequence of their mental illness is not, fundamentally, at fault for their behavior. They BECOME at fault for that behavior when they, while lucid, are confronted with the harm they're doing to others and refuse to take steps to protect those people.
At what point is Wanda lucid? When she leaves the hex and threatens soldiers attempting to rescue her victims? When Vision confronts her directly about what she's doing? When she finally undoes what she wrought at the end? At some point in the duration of the show, she becomes responsible for her actions - at some point she's able to look clear-eyed at herself.
When the show ends, she's suffered another loss, probably among the biggest in her life. She isn't being treated for her illness. She isn't seeking help from someone with the means or ability to help her. She's self-isolating and expanding her capacity to do harm if/when she has another episode with a literal "book of the damned." She is NOT acting responsibly, and putting other people at risk.
That is what crosses the line for me. I don't trust Wanda to manage this on her own, because she failed catastrophically the first time around. She's knowingly putting other people at risk by doing so again. It's not about punishment, it's about harm-reduction. I thought this show was about Wanda dealing with her mental illness. Even superheroes should seek help if they know they are a risk to themselves and others. And she's not doing that. If she had, I think WandaVision would have really broken some new territory. It would have sent such a strong and positive message to MCU audiences. One that I think many of them need to hear. But no, we're onto Doctor Strange 2 because everything is supposedly connected in the MCU.