I am Russian by birth and still lived there till the end of the 1990s. Kefir was that weird slightly sour thing I was occasionally forced to drink in my childhood, and the only benefits I ever heard people discuss were related to weight loss. I grew up with kefir and I never heard of it being better than other cultured milk products. It was also an occasionally lumpy drink... so I suspect there must be some production differences.

My mind still boggles at all the aura of coolness it has developed here. Although I do, as an adult, finally appreciate the taste.
Ironically, yogurt was so exotic when it appeared!