> Floats can be used to position boxes to the left and right edges of their container box No, that's not exactly what float means! Yes you can accomplish this using floats, but we haven't since flexbox and grid landed. The element is taken out of the normal flow, and this is a confusing way to build layouts for those studying CSS. `float` is more of a typographic tool. If this article calls itself pedantic, it needs…
Any introduction to HTML/CSS really should explain the fact that when these technologies were created, they were solely meant to render documents online. It was basically created to be like a Microsoft Word but for files on another person's computer. So most of the early properties (like float) were for typographic layout.
CSS and HTML are loaded with legacy warts that can never be removed without breaking backward compatibility.