The price war was unintentionally started just as demand began to be wholesale destroyed by the response to the COVID pandemic. Supply was reduced, but demand was reduced even more by a halting of the global economy.

Saudia Arabia was trying to bring Russia in line with OPEC+ price targets, but Russia has enough state cash reserves and a much lower state budget break even point (~$40/barrel vs Saudi Arabia's ~$80/barrel), so here we are.