I think you are kinda taking this out of proportion. TBFP isn't "neutered" by discarding a throwaway gag, nor will the majority suffer in the absence of rape horse. Trust me. It'll be fine. Matt (and Pat) weighed their options, made a personal assessment and decided they prefer not to impact a subset of their viewers negatively if it can be helped. Some willing consideration is really not that big an imposition, and it doesn't set some kind of dangerous precedent. The guys will do whatever they feel most comfortable with.

You know, it's not entirely unlike that time when they released their first JoJo All-Star Battle video and later amended it with some corrections to things they had gotten wrong. They really had no obligation to make those corrections, or write that public apology, but they felt most comfortable with doing that anyway. The most fundamental difference is probably that this request about toning down the joke was a lot less incendiary than the response to that JoJo video.

All in all, my impression of the Zaibatsu is that they're a bunch of good dudes who want to do right by people. I think that's something to be commended.