Why are Russian players still welcome
If you see Putin's account, just block him...
Why are Russian players still welcome
Because the US Treasury has exempted telecommunications services from sanctions against Russia. Many telecom companies have voluntarily cut services in Russia, but many have not. Some choose to continue services for various reasons. Some are financially motivated, which was discussed here earlier in another topic. Of course the discussion of financial motivations, and specifically the chess.com management involved, got the topic locked. This is not something you are supposed to ask about or discuss.
For further commentary on the financial reasons some companies continue to do business with Russia, you may want to listen to Bill Browders comments. He is CEO and co-founder of Hermitage Capital Management. At one time the largest foreign portfolio investor in Russia. You very likely are going to get much better information researching it on your own, rather than rely on information here.
Why are Russian players still welcome