Is it done for the sake of transparency or is it a software limitation? If it's the former, then it's just clutter and almost as harmful to the health of a thread as public ban messages on 4chan-based imageboards. It isn't like you know what, when and why it was deleted, only that something used to be there.

Just my two cents, anyway.

This is how most 2ch-like softwares have traditionally handled post deletion. Kareha simply followed Shiichan and 0ch and others which were doing it even before here. It's written firmly in the software I don't even think it can be turned off.

I mean, 2ch's software is kind of shit. Remember when it was about to go down in the early 2000s until the UNIX board optimized it a bit?

The software of 2ch is even worse than kareha lol it can't even delete posts, thats why "deleted" posts have all their fields replaced with あぼーん and im pretty sure mods had to do that manually, probably still do? would explain why moderation is so rare