movies certainly involve a lot of people! many architectures, sculptures from ancient time to this day involve a lot of people and are still considered art!
I would say any form of creative expression combined or solo is art!
I mean, lets take a game like witcher, while its a huge team it still has, creative expression in every individual works there, story writers, quest makers, the attires designed in the game, the world created etc!
I dont believe in the whole work is art only if made by small teams with strapped budget! I mean ya the word creative is often abused by big companies like say EA or ubi but that doesnt really mean all games arent art or that they have to be indied to be called art!
Her story was a nice expression made in the medium, certainly amazing work by the actress and the dev but i would bill it under interactive video medium rather game if you look at it!