default Style vs. default Fonts

I want to quickly apply my Default Fonts settings in Preferences/Interface to existing RTF items. I expected to be able to do it by selecting all text in each item, then selecting Default from the Style dropdown menu, but that applies some other default settings.

Is there a way to make the default settings used from the Style dropdown menu match the settings in the Default Fonts preferences?

You can create your own RTFs in your favourite styles, but it seems to be against the idea of RTF - keeping looks that the author had in mind during storage of the document - to expect RTFs appearing with styles like e.g. HTML pages with CSS style sheets you can influence.