Seems to be because in the original example each of the divs have an 'onClick' assigned to them, so 'tabindex' is the right way to make them focusable by a keyboard user.
<v-list-item @click="method">
<v-list-item-title>Option 1</v-list-item-title>
</v-list-item>This is an insultingly poor opinion to hold of your peers.