That's why China, India, and Vietnam have continued to purchase Russian oil, even if resorting to barter agreements such as Vietnam's procurement of the SU-35 [0] and India's agreement for a JV to domestically manufacture the SJ-100 [1] (which also helps their French partner Safran recoup costs, as Safran is part of India's domestic jet engine program and was a partner in the SJ-100 project before sanctions began).

And it's not like Asian countries are purchasing less from other sources either - they're just using the Russian barter to force MFN deals and discounts from other suppliers.

[0] - https://defencesecurityasia.com/en/vietnam-russia-su35-fight...

[1] - https://www.reuters.com/world/india/india-signs-pact-with-sa...