To clarify, any link styles defined in Global Styles > Typography > Link do not override the styles for non-dropdown links in the main menu, but they do override dropdown links in the main menu. This case specifically is not referring to sub menu items, only the main menu items, which are either non-dropdowns or dropdowns.
Ideally the specificity of the Nav block items links should override the Global Styles for both non-dropdown and dropdown menu items.