The argument is flawed because it premises an absolute right which does not exist.
But if you want to rename every quote, then power to you, if someone asks me to do that on my site, the response will not be friendly to be brutally honest.
I happen to agree with the sentiment, and I have actually had this discussion with the London police back in 2016 over some idiot kid that decided for whatever reason to send nude pics via PM on a mod site for games. He sent them to what he assumed was someone his own age, turns out not so much. It was a 50some year old guy who then pretended to die and had his "brother" join the site and posted about his death.
I am actually the one that contacted the London police in the first place, when this kid told me what he had done and then saw his own pics on some other site someplace. I did give them copies of private messages and stuff like that,
if it was relevant. Then this turned into huge mess with them threatening me with legal action if I did not turn over years worth of server logs, not just on the IPs involved, but they wanted every log of every page view in the site history and every private message these two had ever sent to anyone, whether they had been deleted or not.
I don't know how everyone else does it, but I rarely keep more than 30 days worth of logs. If I am troubleshooting a particularly weird problem I might swap logrotate rules for a bit, but I certainly have no use for what page little Johnny viewed in 2003. And I especially have no use for a private message that you deleted 5 years ago from your own account. Eventually they got told to try coming to Denver to arrest me. We will see how that goes.
If you are going to administer a big board, then get familiar with or have someone write some custom queries for either command line or phpmyadmin or whatever. I have a bunch of predefined ones for vbulletin and now that we are moving to XenForo I will change those. Then you can just paste in a user_id or user_name and have at it.
The idiots that write these laws, in any country, assume we all have the resources of Google. And they will ty to bully you if they think they can. Do some stuff so that you can prove you made a good faith effort, but that is as much as they can reasonably expect and they know it.