I don't see how? It seems that your question has been answered rather adequately...even now, looking at the Kickstarter pledges once again, I see that all it says in regards to your settlement and title is this:
"BARON/BARONESS (digital)
• Baron/Baroness Title in-game
• Choose your town/stronghold & name it"
Nowhere does it say, at least not immediately, what constitutes as a baron. The devs have admitted to making a mistake when naming the pledge packages initially, but in terms of functionality, there is no difference between a simple mayor and a baron. As far as the pledges are concerned; Kickstarter baron = current mayor
I also don't see how you're missing out on anything when the two are almost exactly the same, nor do I see how you're being forced to choose between two things you had though you were getting when there is only one there. Interestingly enough, there wasn't even a mayor tier during the Kickstarter due to that mistake...
What we were all trying to explain to you (as far as I can see) is that you are indeed receiving the same rewards provided in the Kickstarter, if not more. There's nothing stopping you from becoming a baron if you find a duke who's willing.