LONDON — When Daniel Birnbaum announced last summer that he was stepping down as the director of the renowned Moderna Museet to join a virtual reality start-up, it raised eyebrows in the art world.

After all, the Swedish curator was at the top of his game, working with some of the art world’s most prestigious institutions. In addition to the Moderna Museet in Stockholm, Mr. Birnbaum had led biennials (including Venice, in 2009) and a prominent art school (Frankfurt’s Städelschule). He had been a jury member for the Turner Prize in Britain and organized countless contemporary art exhibitions.

Why would he leave all this behind to work with VR, a technology still in its infancy?