Surely they didn’t expect any weaker reaction???
This game is very dangerous a lot of over reacting here.
Russians know all about pretexts laid to justify Western aggression from Napoleon to Hitler. The West has a way of laying blame at Russia’s feet for its wars.
So this is to cut it off at the root. Any further deterioration of relations will be the West’s fault. All Russia can do is exact a high price for the current Russophobic mood gripping the West.
I would say with the current round of expulsions, the message delivered is also a deterrent to further anti-Russian measures. If the West chooses to pursue them, then the low state of relations will hardly get worse.