I suspect we'll address this by just going back to older ranking algorithms for search. We'll go back to the primary signal of good content being links from trusted sources. People gaming the content based algorithms will eventually cause their own downfall.
In the past SEO blogspam was done by cheap freelancers, and there were several agencies selling the service.
Experts identify blogspam quite easily, but laypeople eat it up and use as reference in conversations and to make decisions.
Google has known about it, has been in contact with such agencies and companies, and has been refusing to do anything about it for the longest time.