She had a very strong and well-documented personality and belief system, and was meticulous about how she dressed and appeared in photographs. The only real topless photos of her were taken by one of her lovers, and in them she is in the process of doing one of her elaborate hairstyles. There, are many, many pictures of Frida Kahlo that reflect her pride, political convictions, and self-image, but some dickwad goes and shops her head on a cliched pose of a woman gripping a gun and it’s Tumblr sensation, complete with tags like #sex and #gun and captions like “Frida Kahlo, a loaded gun and calm face. There is so, so much going on behind those black eyes and inside that mad brain while she looks at you.”
A complex, real-life woman of tremendous agency has been reduced into a series of easily-digested badass cliches, and I’m not surprised it’s much more popular than any actual photograph of her.