Even though this is locked, I do have something to add;
Just because someone got banned for a certain action or specific post, it does not mean the entirety of their post content should be censored or erased, sometimes people known in the past for thoughtful, inspiring or just worthwhile comments make mistakes or fall off the wagon.
As Angryboy says, just because someone gets banned does not mean we should sever every tie with them, furthermore sometimes an entire topic could have blossomed from one post of a now banned user, in that case the entire topic would not make sense to a new comer unless all content was left in place.