Actually, the earliest browsers pre-CSS weren't just viewers but had also editing with primitive styling, though it's difficult to imagine in today's CSS-heavy

Actually, the earliest browsers pre-CSS weren't just viewers but had also editing with primitive styling, though it's difficult to imagine in today's CSS-heavy web. Personally, I think adding a complete new item-value syntax and value space on top of HTML/SGML (which already has attributes for exactly this purpose) was completely uncalled for, and to this date we're hearing about the structure/presentation dichotomy which just never made sense as a justification for adding additional syntax.