It is public knowledge. Not sure about the documentation level.

No, I think it can removed in the administration settings of an instance.

2, you know how to program (is it configurable through the normal instance setup or do you have to sift through the code and then maintain your own fork with it removed?)

You don't need your own fork, all of those filters are editable in the admin settings.

I'm on piefed.zip, I can comment "This" just fine:

• https://piefed.zip/post/938948#comment_3538979
• https://sopuli.xyz/post/39615556/21609511