Of course it would. But then there should be a process that identifies such pilot before they even get on the plane, there are two crew in the cockpit, so if on

Of course it would. But then there should be a process that identifies such pilot before they even get on the plane, there are two crew in the cockpit, so if one crewman does something unsafe or inappropriate, the other person is there to notice it, call it out and, in the extreme case, to take control of the plane. Also, if the guy or gal has alcohol problems, it would likely be visible on their flying performance over time, it should be noticed during the periodic medicals, etc. So while a drunk pilot could be the immediate cause of a crash, it is not the only one. If any of those other things I have mentioned functioned as designed (or were in place to start with - not all flying is airline flying!), the accident wouldn't have happened. If you focus only on the "drunk pilot, case closed", you will never identify deficiencies you may have elsewhere and which have contributed to the problem.