Many users no longer feel safe participating here and don't feel comfortable with SE having data about them. While there is a way to delete your account which will result in all your posts being dissociated and your username replaced with a generic "userNNNN", that isn't enough.
Your old username will still be visible in comment mentions (@terdon) and can still be found in answers ("As terdon mention in their answer...", linking to the now dissociated answer). This means that users, and especially those who have chosen to participate using their real name, are still not safe.
If someone has been made a target for trolls, deleting their account won't help them. Their real name will still be visible in the comments, or in other answers. They will still be targets. Given the current extremely tense situation, this is a far greater danger than it used to be. It is essential that SE give folks a way to entirely remove themselves from these sites.
I am not a lawyer, but I understand there may also be a legal obligation to do this, at least for people affected by the GDPR. Deleting my data should include deleting all mentions of my name that can link me to my activity on the network.
But whether there is a legal obligation or not, there is clearly a moral one. The current situation means that this network has put its users in danger, so it should provide a way for those users to protect themselves.
So, please provide us with a way to completely remove all signs of a user's presence on this site. I understand the technical challenges in this, and it may even need to be a manual process, but this needs to be done. Or at least done better than it is at the moment where it is trivial to find out the original username in a page where there have been multiple comments.