To add to this, the context of the original photo is a home in Hollywood in 1923 from a member of the (obviously) deeply prejudiced "Hollywood Protective Association," with signs installed as part of a push by some residents to evict the Japanese-American community and curb additional settlement by non-white people.

As far as I can tell from a cursory search, there was no real material motivation at all, just racism and xenophobia following an increased number of Japanese migrants.