I mean, that's like asking whether marathon runners have a future now that we've got cars. Exercising one's brain/having pleasure through the game could be an end in itself, and is independent of how machines perform.
This really suggests that going the path of being the strongest is no longer sensical. Why would a human try to be the best calculator in the world, knowing it will never beat any calculator ever? Just to prove itself to other human caculator wannabes? Senseless.
This is a real paradigm shift and we still need to understand what to do. But obliviously ignore AlphaGo is akin should be unfathomable for a professional aspiring player.
As a professional, the first question to ask is what will AlphaGo bring to Go Theory. We still dont know how much stronger it is than Lee Sedol (or how far it is from "God"). Pushing it to its limits will show us insights we havent found yet and we will update ourselves as players to the most current theory.
The second step is answering the following question: Can human + AlphaGo beat Alpha Go? A human potentiated with AlphaGo's reading power can intuitively pick variations that would give it an edge? If so, we have found that Go still harbors a human secret that is jsut overly compensated by reading.
The last step would be, even if human participation gives negligible results, can human + Alpha Go create better games than Alpha Go?