Could it be that the source of your skepticism is the fact that you have over the last 2 years seen many comments here on HN asserting that Russia's military is probably incapable of maintaining an effective strategic nuclear capability whereas my comment is the first one you've seen that takes the opposite position?

According to one comment I saw here a few weeks ago, Russia's nukes are probably made of wood.

I suggest searching the web for "Russian nuclear weapons modernization", restricting yourself to credible news outlets.