This is the type of news that gets people seeking alternatives with Bitcoin this would have not happened or if it did happen we would have been able to identify something fishy happened. In fiat money can be given to politicians and there is no way to track it if this money was in Bitcoin everyone not just other rich people would be able to see how much they were given on the blockchain and track when they spent it and where they put it. You might not know what they have bought or if they own the addresses they sent the Bitcoin to but it would be easier to investigate and we would probably see less politicians trying to cheat tax. There is no better advert for Bitcoin this proves that Bitcoin and the Blockchain would be something that every person wants but they just do not realize because the news will not cover that the Blockchain could have stopped this instead they only report on Bitcoin dropping in price and other negative news.
Please, corruption would only cease to exist if the concept of politicians were to entirely disappear. Other factors have close to zero relation on them avoiding the rules that they themselves, as OP said, made. It's really nothing new tbh, it's just that there's a lot of know-it-alls on the internet that seem to disagree with that fact, though whether it's actually their own belief or was simply hired by some random dude with money, we'll never know. Really, if people were to just stop for a minute and think, they'd realize some arguments are darn stupid.
No if we could identify when politicians are committing crimes and punish them then the corruption would die out. Atm this is impossible because they can hide behind fiat and the lack of transparency of the currency and government. The only times we hear about corruption is leaks like this but the news are already trying to make it sound better then it is. The Blockchain would stop this corruption by politicians because there would be many eyes on their spending and where they deposit their money. We have 100s of people watching the Satoshi addresses just in case there is a withdraw and people would watch the politicians the same.