I'm sure the governments will find a way around the limitation of the number of coins in bitcoin if they really want it.
Final number of bitcoins is limited to 21 mlb coins, and if the govenments will decide to brake this rule, they will need to breake bitcoin protocol, wich was not possible possible so far.
There are also estimations that 25% of bitcoins have been lost for good.
Again, if they really want it they will find a way, just look at what they did to gold, at first fiat was completely backed by gold and then the government began printing more money than the gold they had in stock since at the time the dollar was defined by a weight on gold, in fact the word dollar was a form of weight for gold similar to pounds or kilograms, but they circumvented this by printing more fiat, it is possible that in the future governments get bitcoin and back their fiat with it and then they print more fiat than the bitcoin they have in store.