[spicybright]

Can you elaborate a bit why? I've don't think I've seen a time where most sites were generally semantic

[jimmygrapes]

Accessibility is the main reason, I believe

[tambourine_man]

Search engines, screen readers, ancient browsers, future browsers, etc.

The important concept is that HTML tags should convey the meaning of its content, rather than merely being a target for CSS to define its appearance.