What problem does this feature solve?

When using setup(), it would seems more natural to bind the ref property to the template ref attribute.

Bonus: Allows Ctrl/Cmd Click "Go to declaration" in IDE's :)

What does the proposed API look like?

<template>
  <h1 :ref="titleEl">Here is my title</h1>
</template>

<script>
export default {
  setup() {
    const titleEl = ref();
    return { titleEl };
  }
}
</script>