What percentage of HN is simply promotional content?

Like posted or "gets to the top page?"

Turn on "Showdead" to get a feel of how much the promoters want HN to be simple promotional content.

I feel like letting spammers run wild(er?) would ruin HN for the spammers themselves, as well as regular readers like you and me. Advertisers and spammers are notoriously sociopathic, however. They just don't care about tragedies of the commons, using up all of a particular resource, externalizing their costs on those being spammed or advertised to, or any other factor. No single raindrop believes it is responsible for the flood, after all.