A couple of things.
“Drone” doesn’t mean anything about speed. A drone is no faster or slower than than any other weapon with the same propulsion system.
And “shot down” doesn’t mean bullets. Air defense systems generally use extremely fast missiles.
Russia is still profiting handsomely from oil sales, in large part due to India buying so much of it.
https://www.reuters.com/markets/commodities/russia-boosts-oil-revenues-shipping-trading-network-grows-2024-06-14/