Comment by crabmusket

Exactly this. I really wish browsers would use semantic html to make content more accessible for me, a sighted user! Why does my browser not give me a table of contents I can use to navigate a long page?

I think the parent has a good point: browsers don't do anything with these tags for sighted users, who are unfortunately the majority of developers. If they were to notice benefits to using semantic tags, maybe they'd use them more often.