I’m not the commenter but I
Imagine it just boils down to what you are archiving, but in any case I don’t think the commenter really understands what html is being used for here. The “preserved” material doesn’t have to be html, the html is just to set up the directory navigation. In the blog post, they even mention that each type of material is its own website so that each website can be designed to handle that file/data type.