Are you serious? I'll indulge as you are probably scaring some newbies... SEO will never die. For every search query there are thousands and thousands of options to deliver to the searcher, how else will Google know which is best?
Only social signals you say? That is in the definition of SEO by the way. But what about the thousands of niches no one wants to be social about, porn, medical, weird hobbies, etc?
"Soon Google will just read your whole page, see what you're about, and rank you strictly on content!" Nope, too much resources needed, you give Google far too much credit. The search engines need SEO's. The search engine is our bi$%h.