I understand, however in most of cases, process can be unblocked by I/O event bar. So it better to click the bar instead of remove process out of CPU and later let user kill it. Of course, in case that process can't be unblocked, it make sense to remove it.
"however in most of cases, process can be unblocked by I/O event bar"
You have to wait for the I/O event to be available in order to be able to unblock the process, which can take several seconds. This is why in the meantime it's better to let another process use that CPU time instead. Trust me, I made the game ;)
Now obviously, yes, if the event is already available by the time you notice the blocked process, then it makes more sense to just unblock it.
And no, removing the process from the CPU does not mean that you're going to let it get killed, it just means that you're gonna put it back on a CPU once it's unblocked.