I recently attempted to remove React as a dependency just to see what would happen. It turns out different browsers are still incredibly inconsistent when it comes to event handling. For example the select event on an <input> element somehow doesn't fire at all on Safari during my test, and doesn't fire when the caret is merely moved on some browsers. Using just the native browser functions isn't just fine, even if you don't need all the React features like components or state or props. It turns out React DOM is valuable as it papers over browser differences.