Maybe its time the FAA updates its FARs?
According to FAR 121 ,Aeroflot did not break any of its rules..as reckless as its pilots actions may have been..
I don't think the reg you quoted means what you think it means. All that says is IF a part 121 operator does not have an approved ground deicing/anti-icing program, they may still take off when weather conditions could create structural contamination on the aircraft if they do a pre-takeoff contamination check within 5 minutes of takeoff from the exterior of the aircraft. If there is no ice or snow adhering, they may take off.
If the airline does have an approved ground deicing/anti-icing program, then that program must be adhered to.
Basically, if I had a little commuter operation out of San Juan, it might not be worth it to me to come up with a ground ice program in my ops specs. If a freak snowstorm hit the Caribbean, I could still take off if I was able to perform the pre-takeoff contamination check AND the airplane was clean. If anything was adhering to the wings, or any other critical surface, no takeoff.
With that in mind, from that video the Aeroflot plane would have been in violation.