If Maduro was holding Bitcoin instead of gold, specially gold outside of your borders, he wouldn't have had that little problem. Of course Maduro is probably too computer illiterate to get the thing done.
You could make the argument of "if he was holding his gold inside his country he wouldn't have been denied access". Well still, it would make sense to hold Bitcoin and not gold, specially when you have an empire like US always threatening anyone with entering your country and taking all of your gold and oil reserves as they will do with Venezuela. With Bitcoin they couldn't be able to take them as you could have safe backups overseas.
This is an unbeatable logical argument for the bullish case of institutions holding Bitcoin. Im not saying they should dump all of their gold, but definitely dump a certain % and diversify with Bitcoin. This will happen sooner or later, and it just takes a first mover for the rest to follow, they will not be able to afford not having some due game theory, similar to not having powder back in the way when when wars were fought with swords.
There's always a problem when an asset is held by a third party.
The same can be said with any fiat, in my opinion. There is a risk that the bank who holds a country's reserves (especially if its jurisdiction is overseas) goes rogue and it refuses to move funds when it is instructed to. That risk is the same as what has happened here to Mr. Maduro's gold withdrawal.
Bitcoin combats this issue given its decentralization and trustless nature, as there needs no third parties to get a transaction processed and done.
So you're absolutely right, given that bitcoin has the positive traits of gold which makes it valuable (decentralization of currency supply, no single entity issuing the currency), whilst improving on the convenience, portability and trustlessness of remote transactions, it does make sense for countries to start holding bitcoin in reserves.