The Golden State Warriors will not be challenged by any team in the 2017-18 year unless one of the other contenders makes a big move. It would take the Oklahoma City Thunder, Houston Rockets, Cleveland Cavaliers, or the Boston Celtics to make a trade that would keep their star core intact while adding another. It’s unlikely that we will see that happen this year.
There are teams that are putting themselves in the position to outlast the current Warriors. Teams that would challenge them in the coming years after the Warriors, presumably, win a few championships. Teams that could eventually topple Golden State.