I see a big difference. Driving drunk/high impairs your judgment; it means you are less capable of knowing what a safe speed is (as well as being less able to judge many other factors). So it obviously increases risk.
Violating the speed limit, assuming you are sober, might not increase risk at all, because the driver has more information about the conditions in the particular situation than whoever set the posted speed limit, and therefore is better able to judge what a safe speed is. His judgment might be (and often is, if typical behavior on highways in the US is any indication) that the posted speed limit is too low--that speeds higher than that limit are still safe. I don't see any basis for saying that he must always be wrong and the posted speed limit must always be right.
> I seen how law enforcement changed driver behaviour in my country of origin
I didn't say that law enforcement doesn't change behavior. Of course it does. The question is, at what cost? And is the cost less than the benefit? Could the same (or greater) benefit be achieved at a lower cost by some other method.
Your own description suggests very large costs that you do not appear to be taking into account: you speak of "extreme amount of corruption" and "huge bribe". What cost does your society as a whole bear as a result of these things, compared to a society in which people are held strictly responsible when they cause harm and know they can't bribe their way out of being punished?
While I don't think that anything legal must be "ok" and law is perfect I still don't agree with you and there is serious reasons for that. First of all one can simply be "lucky" with careless driving or just straight defective brakes.
Second I seen how law enforcement changed driver behaviour in my country of origin. Even with extreme amount of corruption it's still forced almost everyone to use seat belts, pass vehicle inspection regularly and avoid breaking the law if there is chance that will end up with loss of their driving license or huge bribe. I totally sure that without proper enforcement that would be never achieved otherwise.
Third is that I seen the difference between driving behaviour in the UK and Asia and while UK system cause a lot of false positives lethality numbers make a big deal. Even if enforcement is not the only measure to calm traffic it's important one. I really can't see how one can justify that 3x-10x more people going die.
Last reason is that I simply not believe that society on it's own can change driver behaviour as effective (if at all) as enforcement. Fines and tickets work because they are market mechanism like fuel and horsepower taxes, paid parking and London's congestion charge, etc.
Also there are plenty of other laws that limit overtaking on sidewalk, illegal parking and many more that only work because there are enforced. Remove them and streets of any country will slowly turn into hell.
UPD: Grammar fixes.