Why are communists better at perserving races better than cuckservatives?

[Daqirius]

Old ussr map ensured that each country under their rule ensured racial and cultural soverignty despite being supposbility against it

north korea is realitvily homogenus due to their tough restrictions

China can also count because despite having similar ethnic groups they all orignating from the same source, have similar cultural practices and phenotypes

note that while its not 100 percent pure there is still an over 90 percent hegemonic ethnic group