And not just because of the obviously higher risk associated, but also because it appears not to be effective against the new strains. (Especially the new South Africa strain). Unlike for example the Janssen vaccine (goes by their parent company of Johnson and Johnson in the US) which was actually validated in South Africa or the rna ones which are just a technical masterpiece.
Keep in mind that the real shortage of vaccines is production locations right now. And the type of production of the Janssen, AZ and the Sputnik vaccine is all similar. So why even produce more of the worst vaccine in any of these locations.