To me this doesn’t specify how I would actually hide an HTML element that is not an input and doesn’t have a CSS selector to target. Should I use style="display: none"? To me this seems like the worst option of the three equivalent options we have (class="hidden", hidden and style="display: none"). I think I would prefer to use the hidden attribute as it is short and doesn’t depend on CSS styles.
As this mentions labels, I think it should also link to Providing Accessible Names and Descriptions | APG | WAI | W3C to give more information about labeling content.
Apart from that, +1 from my side.