Is Russia a net importer or a net exporter? That tells the tale. If they’re a net exporter this is actually beneficial to their economy.
Oh they have a huge trade surplus because exports are what their entire economy is based on. It isn't beneficial to their economy, it's necessary, because US and European sanctions are making Russian exports more expensive and debasing their currency is their only way of staying competitive.
Russia conducts far more trade with Europe than it does with the United States and the cheaper ruble will make its domestic products more competitive with the products it imports. This will drive domestic consumption and spur economic activity in Russia over the longer term. Sluggish economies in Europe which don't have this flexibility in their currency will only grow more stagnant as their exports to Russia become more expensive and Russian exports to Europe get cheaper.