If you want to make a good argument as to why they are all the same, while there are clear and important distinctions between the two major us parties, I'd love to hear it.

But if you are going to make stupid arguments like "they are all the same because they agree on this one thing!" Or "they are all the same like rectangles are all the same!" Then you are going to get called out for it, and pouring on the sarcasm in place of an argument doesn't make your initial point any less stupid.