I was able to resolve this by extending the ListItem.
First, get ListItem
import ListItem from '@tiptap/extension-list-item';
next, extend it by setting it to only allow text content (Turns out there are schemas that set what can go in a node)
const CustomListItem = ListItem.extend({
content: 'text*'
});
Finally, add it in:
mounted() {
this.editor = new Editor({
extensions: [
StarterKit.configure({
history: true,
}),
CustomListItem,
],
});
}