I don't know if Blocking Someone is Always the right thing to Do
I think it's important to leave open communication
They may regret what they did a few weeks or months later and want to reconcile. If you have them blocked, then they can't contact you about their regret.
They may just be worried about you and want to ask if you're okay. If they're blocked, they can't do this
They may just want to apologize for something. How they handled the breakup, or treated you. They can't if they're blocked
I just think blocking someone should only be reserved for abusive exes.
I just remember when I left one woman, about a month later I went back to discord to talk to her about what happened, maybe get back together, and I saw she had deleted her account. At that point I gave up