If you think about the future of search, the possibilities can rack your brain to no end. Though you will notice that every perspective always leads back to one fact, information and problem solving content will never stop receiving search traffic.
Even if we get to a point like Star Trek (where Google really wants to be) you will still have to have a source for the information that is brought back to the user.
Someone has to make that content. It raises the bar of "who is writing the best content" and "what content will be best for the user" seeing as the end-goal would be one true answer that was returned from the engines, perfectly catered to the query. If you consistently write the absolute de-facto standard on a given realm of content, it is likely that you will always get traffic. Your information will be either pulled by engines automatically, or your site, page, blog etc. will be the number one resource.
The thing that you have to realize is that every query, every search is exactly that, a "search" that is looking for information on some scale. Whether it is locally relevant information on the nearest Denny's (hopefully nobody is searching for that, find a local breakfast cafe you animal) or ancient history of Japan, it's information.
This is the point of content marketing. We are solving the problems that Search Engines want to have solved, so naturally we will be the ones represented at the top of the field. Google is lining up our content like picking teams for a dodgeball game, and as we would pick the biggest, strongest motherfucker on the field - they are going to pick the most apt, most authoritative piece of content they can find.
We have to be that biggest, strongest mother-fucking piece of content on the field.
You get to the top of Google by answering Google's queries, that's why every marketer should study user-intent, study queries themselves. Everyone has an end-goal when using search engines. You don't go to Google to twiddle your thumbs and make words come about. Solve that end-goal for someone.
There will always be people searching for information, in any field. There will always be queries, even if they are spoken to Siri or some other form of voice recognition software. Even if the software has an AI that grabs content automatically for the user, that content has to be obtained from somewhere. Google won't be able to archive the entire world's information, and create it too. The creation is where we come in. Especially since 90% of all data created since the dawn of time has been created in the past 2 years.
Google will have to pull information from somewhere. Even if Google falls under, the same goes for all search engines or problem-solving AI's. I'm not doubting that DuckDuckGo could blow up, or god forbid Bing outdoes Google. The point is putting out information that is great enough to answer the questions your users are asking, your market is asking or the users you are trying to target are asking will always be a very profitable endeavor. Just as the content you're making is evergreen, people trying to find answers will always be evergreen.
The mediums to your content may change, but the fact is that the content you make will always be weighted, it will always matter if you're doing it right.
Answer queries, give information, receive traffic, be known to searchers, be the industry standard and have your content live forever.