max -

Perhaps they're afraid that dox/raids could get them in trouble with their hosting provider(s) or other higher-ups, though I can't be sure.

Maybe. Don't think the owner had a problem facilitating raids in the past, though.

opt -

Unrelated to the topic, but I find this rule added on the branch ironic. Almost seems like they're attempting to sanitize their image… I wonder why?

Perhaps they're afraid that dox/raids could get them in trouble with their hosting provider(s) or other higher-ups, though I can't be sure.

max -

The reasoning is actually quite simple. By cloning the master branch of esoBB, I inadvertently became an early adopter of esoBB 1.0.0e1. This version adds things such as the separated RSS plugin. I wouldn't say this is a bad thing, as it means I could catch a few bugs and potentially help make the release stable.
It's also worth noting that esoteric.chat, the most prominent production instance I know of, runs a different branch of esoBB too.

Unrelated to the topic, but I find this rule added on the branch ironic. Almost seems like they're attempting to sanitize their image… I wonder why?

opt -

Block quoting seems to be a little bit broken - it appears that the end tag has to be on a newline, which isn't done for some reason when a post contains a list. Honestly, I'm surprised there's elementary bugs like that still remaining, considering we're not the only people to have used esoBB… Maybe it's a regression introduced since we presumably run a newer version of PHP than esoBB targets?

The reasoning is actually quite simple. By cloning the master branch of esoBB, I inadvertently became an early adopter of esoBB 1.0.0e1. This version adds things such as the separated RSS plugin. I wouldn't say this is a bad thing, as it means I could catch a few bugs and potentially help make the release stable.
It's also worth noting that esoteric.chat, the most prominent production instance I know of, runs a different branch of esoBB too.

Currently known bugs:

• Flood checker making invalid queries and causing error 500 - partially fixed in the fork (by commenting out the faulty code); a real fix would require changing the database schema to account for IPv6
• The email regex is too strict - partially fixed in the fork; note that the current regex in the fork doesn't account for all possible emails (especially ones with quoted local-parts) and the old regex is still scattered across various files.
• RSS feed returns error 500 - fixed by renaming the plugin to avoid collision of class names, patch submitted upstream.
• Many database values are unsigned 32-bit ints which could overflow - more of a risk than a bug, perhaps it's not really significant; note that php only supports directly handling 64-bit integers on 64-bit processors as of now, AFAIK.
• Closing a block quote ending with a list only works when the closing tag is on a new line (minor bug) - unpatched