That is actually a pretty good explanation.
Speaking for myself: our (Boeing) manuals do specifically address dry snow/cold temps and specifically permit departure without being sprayed under these conditions provided the snow is dandelion seeds.
However, those same manuals also specifically prohibit takeoff with any snow on the wing regardless of whether it is actually adhering. Whether it is stuck fast or just lying there, we are REQUIRED, by whatever means, to ensure the critical surfaces are 100% clear of contaminants before initiating the takeoff.
I don't know about Aeroflot's or Airbus's manuals, but the takeoff in the video would have been a gross violation from my particular seat.