>>395260085
It also prevents board tourists from shitposting specific people, because they don't know who is being vagueposted.
Also makes doxxing someone by searching the archives harder.
The ban issues also still apply.
Lastly, it may also partially be a concession to humility and from standing out too much.

There's probably more reasons in favour of letterdropping that I'm not thinking of right now, I'm sleepy.