I don't know much js, but it seems fairly straightforward. Here's some comments:

    // create an element with 'tag'
    const elem = document.createElement(tag)

    // copy properties into the new element one at a time
    for (const k in props) {
        elem[k] = props[k]
    }

    // append child elements one at a time
    for (const kid of kids) {
        elem.appendChild(kid)
    }

    // and that's it
    return elem

Applied recursively, you can make dom elements with very little boilerplate.