They will never trust each other. The need trustless money

this is more of "trade surplus" issue since "a nation has to net PRODUCE or EXPORT something others in world need"- narrative of journalists bit wrong there - also it is not settlement currency issue

"Russia has accumulated billions of dollars worth of rupee assets given its wide trade surplus with India, but it's struggling to use the funds. The rupee isn't a fully convertible currency internationally, making it difficult to use in global trade."