You are 100% correct. A lot of these governments are corrupt to it's core.
Even if governments are corrupt to its core, I think it is still the citizen's duty to still pay taxes despite their leaders being corrupt. Even if they are corrupt, they are the ones leading their country and it is no easy feat. At the very least, they are the ones enforcing the rules and regulations that protect the citizens from harm caused by criminals and terrorist and IMO, they should be paid for that.