I found a plug-in for Firefox that deletes all posts and comments from your reddit account. (Power Delete Suite). Now I am in talks with reddit, to have them delete my account and data.
They say that all content will be disassociated when I delete my account but I had them confirm that they won’t recreate it when I have deleted it. They still say that they will retain the IP used for creating the account. Not sure if this is legitimate data redemption after I have asked for my data to be deleted according to GDPR?
You should be able to Google search your username if you haven’t deleted your account.