One thing nice about React is that it can take care of quoting for you depending on the method call the jsx template translates into (attribute, value, element name). String templates doesn’t have that nice property.
I'm not sure what you're saying is true with lit-html. You don't have to quote attributes with single expressions.
html`<div class=${myClass}></div>`
https://lit-html.polymer-project.org/guide/template-referenc...