I know several people with Nigge in the name - probably less common in the parts of Germany where lower German wasn’t spoken.
It also exists as component in the middle nof names, both with and without r - and does so in other languages as well.
The point of this example is that you can’t just filter and be done with it - depending on what you’re doing filtering, flagging for review or not filtering and acting on complaints are all valid strategies - but there is no version where you can do without staff to either block or unblock names.
edit looks like the slur filter on lemmy.ml censors the name of German journalist Stefan Niggemeier