It would in many ways be much better if this were only a failure of regulation. It’s trivial to change rules and with a catastrophe like this the incentive to do so is there. Looking back at other catastrophes (I always have to think of Chernobyl, I don’t know why) I fear much rather that your view of the causes (mistakes and laziness) might be closer to the truth. That’s not as easy to change.
Something like 1 billion! oil wells have been drilled. And about 100,000 offshore oil wells. Many many accidents have there been?
It's actually a pretty good safety record.
For example, simple elevators are typically designed to be able to safely carry 7-10 times their normal operating weight, including the cabin. I find it hard to believe that "many of their safety systems" just failed - I think it's a lot more likely that a series of really stupid human mistakes are behind this as well as management that is unable or unwilling to enforce (sometimes costly) safety procedures and practices.