Originally Posted by bourbonbasted
They wear the same stuff as anyone in the Midwest or Northeast would.
This seems to be the most important part of your argument so I will address this. I think so some degree you can make a good case for this because, as I mentioned early on, there is quite a lot of crossover between eastern trad clothing. This doesn't mean that they are the same, or that their identities are even largely indistinguishable. One of the things that I wanted to push early on is that when defining the differences between trads it is important to look at tendencies rather than stark differences. This doesn't mean that no stark differences exist, it just means that they exist in a particular context that is rarely found outside the geographical location.
Ok, so let me give an example. You mentioned seersucker and it is a perfect opportunity to look at how things are shared across borders. It is unknown who first introduced the fabric to the U.S. since both Brooks Brothers in the north, and Haspel in the south, claim credit. Whatever the case, we know that seersucker is popular both in the north and the south. The difference between the two is the context in which it was used. In the north, seersucker is mainly a one season fabric (obviously) and was generally unseen in the city. Not so in the south. This nearly year round usability seems to have lead southerners into pairing seersucker with everyday business appropriate ties and shoes. This isn't to say that they don't pair it with white bucks, spectators, and the like, of course. It simply means that the context and social meaning of the seersucker suit was different as well as the way in which it was used.
Let's take another example, FU trousers. Both northerners and southerners wear them, but again the use and social context differ. In the north they were primarily utilized for a very short time of the year and usually in the context of some kind of party or vacation and, again, almost unheard of in the city. This isn't the case in the south where they are not only seen in the city, but are relatively common in many areas in the evening, even at restaurants and evening entertainment. Southerners are also much more likely to pair a pastel colored shirt with FU trousers, a bridge to far for many northerners. Even your fits didn't go that far.
Keep in mind that I am talking about traditional uses of clothing, and the lines between geographical styles are blurring with every passing day due to social media, globalization, and big box marketing. Other than that, I have made extensive posts on the differences between the two trads. I'm not sure if there is something specific in those posts you would like to refute, but I welcome you to do so. Your original objection didn't really address any of my claims, but simply said that they were wrong. I'd welcome a more evidence based refutation if you'd care to.