I believe I've been misunderstood. I don't think they're extremists in a political sense or anything. I think their stance on the harness discussion is on the extreme end of things. Many of the arguments were "Your dog must wear a collar or harness 24/7 or you are an irresponsible owner", and they left no room for alternative views. That falls under the definition of extremism in my books.

dogs above 40 lbs must be in a harness and wear a collar at all times when out in public

I agree 100% with that practice. In my opinion the only time dogs should ever be off their leash in public is when they are in designated off-leash areas. When I have my dog in off-leash areas I leave his harness (with contact info) on too. We weren't talking about dogs outside though. It was mainly about dogs whether dogs should be required to wear their collar/harness inside the home.

Anybody who said they took their dogs collar/harness off would face the wrath of the "you're an irresponsible owner" crowd. No counter arguments would be considered either. One user made the outlandish argument that an apartment dog could escape into a common hallway, get into the fire stairs through a propped-open door, go down 5 stories, open the emergency exit via a crash bar, and get outside. To me that is an absurd scenario to use for an argument, and definitely something that only a person with extreme views on the topic would stand behind.