For those in the know about privacy laws and the such. What is a proper response to reddit's claim that they cannot remove all the information associated to an account without first the user removing

As the title says, Reddit replied to my GDPR request to delete all my data saying I had to do it first, which I suspect is in violation of GDPR law.

Reddit's argument is that to comply with GDPR, they just need to dossociate your account from your posts, so the latter cannot be traced back to you. However, the argument could be made that the posts themselves are enough data to be linked to you.

Is there any type of response that could be framed in legal terms to make reddit really remove all the content from my account?