Project Manager: Now add 3 checkboxes, one being 'N/A' and when you select N/A the other checkboxes are disabled and unchecked. And update the labels, and have additional form sections showing depending on which checkbox is displaying.
Probably not that difficult, and probably a bad example, but with React/Vue/etc. it's a lot easier to deal with complex states than manually manipulating the DOM.
From experience trying to be clever and anti-framework ends up just creating another framework that's worse in every imaginable way.