The thing is that I also analyzed the number of users in Interpersonal Stack Exchange (admittedly more crude, only month datapoints) and asked in chat if there is a drop. The more accurate data provided showed only a barely noticable (if at all) drop.
As Shog suggested in chat, I ask here if we have a noticable increase of users deleting their profile on all sites, separated by all, min 1000 reputation and 5000 reputation. This may be not so noticeable with a stream of incoming new users, but if the current route of march is answered by an exodus of (experienced!) users than we definitely should overthink this. I also admit that it may be not so easy to separate necessary (GDPR!) and intentional (Code of Conduct) influences, but we should look out what the data says.