You are deeply misinterpreting Mearsheimer's conclusion in your piece. He's not saying that NATO has a responsibility to not upset Russia - He's merely (accurately) noting that expanding the West's sphere of militaristic and social influence right up to Russia's borders has led to a clash between conflicting interests. Both sides are responsible for furthering their own agendas, and the agendas are incompatible when they meet. This is Mearsheimer's point; if we didn't want conflict in Europe, we should not have run toward it.
Further, I think you could do with giving Russia more credit than you do - Suggesting that they are a declining power because 'all they have is a large portion of the world's energy reserves, and one of the few nuclear arsenals that shapes the world's geopolitics' is more than a little stretched, even if I see what you're shooting for.
It's worth remembering the chaos they have successfully sown in US and European politics over the past 5 years, along with the effective interference they have run in the West's Middle East policy while assessing Russia's level of power in the world.
Nonetheless, I have been interested to see how much debate he has caused in such a short time - We need more lightning rods like this!