public officials are not that easy in corruption. if you use blockchain in a payment transaction then they can break coins to the smallest part to hide state assets. we must remember that rulers tend to be corrupt. So there needs to be a new rule if the country uses blockchain technology for payment transactions.
When rulers are corrupt, there are sometimes when they feel their hand is tied, it would be hard to do somethings. I feel you that one way or the other, they could try to find another means to keep doing their corrupt deals, but imagine in a situation where everything has gone digital, most governments are already on the blockchain and we have gone cashless, every transaction made by everyone most especially for the fact that it is centralized, will make it pretty easy to track any shady deals, and everyone can easily access these records, then I feel it would really go a long way to bring about some changes in governance, but all still depends on some few factors which balls down from the head anyway.