Since the authors are arguing for removing a lot of current housing regulation, I have a hard time seeing how "the billionaire class of the Democratic Party" would consider them their enemy -- unless, of course they're mistaken for people in class b.
>Since the authors are arguing for removing a lot of current housing regulation
Human beings like to know if the person they're reading is on their side before they take the time to read a long ass article to make sure they are in fact on their side, especially if they're billionaires and think they don't have the time to read long ass articles about housing policy unless they think it's going to an extremely useful to them beforehand. That's the whole point of giving that signal literally in the intro paragraph.