This image is easily recognizable for many people, and many more who aren't as less familiar with Indian history may still be familiar with the image, or at least with the person in the image. Even without historic context, many are able to recognize some meaning from the image, such as Gandhi's peaceful and non-violent nature. The image is even more recognizable to anyone familiar with Indian history, as it's debatably the most iconic photo of the modern history of India. It features the most recognizable person and most recognizable symbol in India.
More info about how culturally significant Gandhi is can be found in this section
More info about the spinning wheel symbolism can be found in this section.