A horde of children chased Conan O’Brien onto the Dolby Theatre stage in the opening moments of the 98th Academy Awards, and throughout an Oscar ceremony that saw “One Battle After Another” win best picture, it was like they never left. A queasy future, both immediate and for generations to come, pervaded over an Academy Award shadowed by war, political turmoil and whatever might happen to the movies in an A.I.-supercharged tomorrow. These were the high anxiety Oscars. At almost every moment, they seemed to be trying to rally a little optimism despite omnipresent storm clouds.