No, they cancelled the previous ban. The new regulation from March 11 permits bringing cash to Russia for personal use. So you only need to declare if you bring more than $10,000.
However, Russia-related General License (GL) 18 authorizes certain transactions that are ordinarily incident and necessary to the transfer of U.S. dollar-denominated banknotes for noncommercial, personal remittances from: (i) the United States or a U.S. person, wherever located, to an individual located in the Russian Federation; or (ii) a U.S. person who is an individual located in the Russian Federation.
Source:
https://home.treasury.gov/policy-issues/financial-sanctions/faqs/1028