The point is fairly straight forward and it shouldn't be difficult to comprehend. It's not about pictures, it's not about nudity, it's not about tits.
Now frankly i don't see the need for a mature section, I simply see the issue is not having to pander to the "kids" of the site, where posts might be reported for whatever reason (swearing as an example), It's about being able to have a grown up discussion without fear of repurcussions. No one likes every other word to be fucking this or fucking that, it degrades the site it degrades the person posting it. However, using within the right form it shouldn't result in someone being reported for it.
As I said earlier, we all just need to grow a pair. Life's to short to get hung up on utter nonsense.
Then by all means, get rid of the swear words thing (which you guys seem to be doing). Like you said, we shouldn't need a mature section. That's exactly what deep thought is for. So, what would be the purpose of this "mature" section? Literally all I'm noticing that that would add is the pictures thing, which is completely unneeded.
The problem lies with maturity. That's already supposed to be what Deep Thought is about. It was civil until the first picture. Some people told them to take it down, then other people got pissy at them before they thought something different, then it spiraled out of control. All that needs to be done is people need to be more respectful of each other. None of the people involved were children.