Wibta if I ghosted my "friend"?

Throwaway account and made up names for obvious reasons.

Basically, I had/have a friend, Joan, who at one point told me about an argument they had with one of their other friends, Anna, who I did not know and have never met. When Joan told me the story of what happened it was clear to me that Joan was actually the one in the wrong. I explained why and that I too would have taken issue if they she had behaved that way towards me. Joan expressed that this ultimately came down to a cultural difference but seemed to understand what I had explained to her. I am not entirely sure but I believe Joan apologized to Anna as their relationship continued. A couple of months later they had another disagreement that just made it best for them to not continue their friendship. As far as I know they are no longer in contact with each other but I'm not sure. I never asked. Not really my business. But in the time since Joan first brought it up we have spoken about the underlying cultural difference on multiple occasions, in different contexts, we've joked and laughed about it but I have always maintained that I would not like it if they behaved in that way towards me. I have always been clear about that. So I'm sure you can see where this is going. They eventually did it to me to. It feels like they planned it and tricked me to create the opportunity to do it but let's give them the benefit of the doubt that it wasn't planned and they just took the opportunity when it happened to arise. Haha. I saw what they did and walked away in shock. At which point they called me and told me that they like to make me feel uncomfortable and laughed really hard about it. I cut the call.

The thing is, by that point, we've had countless conversations about this. They were acutely aware that this would not be amusing to me and I would not find the joke funny and they did it specifically for that reason. So I feel like there is no need for me to explain anything more. I just don't want to maintain a friendship with someone who would go out of their way to impose themselves on me in this way. Do I have to call them and explain it to them to "breakup" the friendship? I don't see the point in it. There is nothing I could say about all this that they have not already heard from me. And I honestly just don't want to have to listen to another story about how they are the victim in all this or how it is part of their healing journey or it turn into another session of "negotiating my boundaries" . I just feel like I have nothing left to give to them and someone else will have to offer them the patience and understanding they need.

They texted me about something unrelated and I haven't responded. Would it be terrible if I just never did? Once upon a time they had mentioned to me that they have abandonment issues and I would not want to make that worse. But also, I just feel so disrespected by their actions and if they so clearly don't care about me why am I prioritizing how they process it over how exhausting that conversation would be for me? Honestly, no matter what I say they will probably just complain about it to some other friend the same way they complained about Anna to me. A person who doesn't want to learn or see an error in their ways will never learn, right? Am I justified in essentially ghosting this person or am I just finding excuses to avoid a difficult conversation that needs to happen?

We're both just too old for this. It's embarrassing