Not quite star trek, but I do know that in The Man From UNCLE Illya Kuryakin, the Russian/USSR operative working for UNCLE was so popular that in the second season he got promoted from side character to full on protangonist and that aired a year or two before star trek. So if an explicitly USSR aligned spy could get that popular to the point the producers felt comfortable making him a main character, I imagine one from the far off future where Russia is more of a off hand mention in comparison would be even less controversial
Funnily enough the 2015 movie version of him is way more critical of the Soviets than the show made in the height of the cold war ever was
Not quite star trek, but I do know that in The Man From UNCLE Illya Kuryakin, the Russian/USSR operative working for UNCLE was so popular that in the second season he got promoted from side character to full on protangonist and that aired a year or two before star trek. So if an explicitly USSR aligned spy could get that popular to the point the producers felt comfortable making him a main character, I imagine one from the far off future where Russia is more of a off hand mention in comparison would be even less controversial
Funnily enough the 2015 movie version of him is way more critical of the Soviets than the show made in the height of the cold war ever was