Legalism implies to me that they are saying you have to live this way in order to attain salvation. As far as I know, that isn’t their stance. They say, you have to live this way to be a part of our community. So, to me, it’s nothing more nefarious than a set of homeowner’s association rules.
They do follow, to some extent, a works-based form of salvation. It is more than a nefarious set of homeowners rules. It is more like dress this way, live this way, or you will one day most likely end up in hell-fire.