Sometimes those interesting features are not easy to find.

When looking up on how to do something for the web, one get tons of answers describing how to do it with javascript and usually with js frameworks. The simple methods (which do not cover all cases but are sometimes enough) are usually buried under.

So unless beginner learn by heart all the html tags (and that is not beginner friendly) they won't know those basic features, so I think that's cool to have a reminder.