That's a good question.
There's probably no stronger moment for Vladimir Putin than right now, because of the figures you just cited but also because of the timing. We're in the middle of the winter, and Russia exports gas to Europe. In the case of Germany, 40% of the gas comes from Russia, and in the case of Italy and Austria, it's 100% of their gas. This is the moment when they have maximum possible leverage, and what that means is that the Germans, Italians, Austrians and others are going to do everything possible to break ranks with the Western alliance and not be too tough on Russia.
As far as the SWIFT sanctions go, you're correct that Russia has these enormous reserves, but that doesn't really matter so much if you're in a situation where you're basically cut off from the rest of the world financially. Your reserves will run down very quickly, and life will get bad in very short order.
Nobody should underestimate the pain of SWIFT sanctions, but nobody should underestimate all the collateral damage that it will do either.