I think he's trying to get that soft power he used to have where he could make threats and the west would appease him to some degree to avoid nuclear war.
Though IMO whether the nuclear arsenal is working or not, those bluffs should be called each time, otherwise that line will keep getting pushed until it reaches the point where a demand cannot be met or compromised and then we're in the same spot we'd be if we had just called the first bluff, except Putin also has the benefit of each previous appeasement.
After the fall of the USSR so many of their nukes went missing were grabbed by former party members and sold off to the highest bidders for fissilable materials to start nuclear programs of their own and to make the sellers rich (cough the new group of Oligarghs whose wealth seemingly showed up overnight).