Definitely if you were still dating, not replying would be rude. But the relationship is over. If he replied to you, you’d say something back and then you’d be upset he didn’t reply to that. Then if he did, you’d consider it rude not to reply yourself, then you’d say something etc Then it would never end. At some point someone needs to stop.

His message to you that he has only positive thoughts was to leave this on good terms and also a delayed reply to your declaration of love at the break up (he possibly thought of what to say). When he said he has good things to say about you, you reply with the nice message back and it’s a closure. It’s done.

But then you initiated communication with him later (not as a part of closure conversation) about what clubs you went. It doesn’t sound like a follow up to anything as he didn’t ask you anything and you aren’t in a relationship or dating. I don’t think he is a jerk here. What did you want him to say?