—”A weak ruble probably benefits Russia, and if Putin wants to sell oil, he can sell it in dollars.”
Long ago I heard Milton Friedman answer this question in the blink of an eye.
He said if that were true, ‘The highest inflation countries; would be the leading exporters’.
The students found that humorous.
Without trying to advocate for one position or another, The pundits usually claim that a weak dollar helps our exports. Maybe they are talking about sheer tonnage, or quantities, rather than the value of the currency received.