He probably was until his last near brush with death a couple of months ago. At this point, ISIS is basically gasping to stay alive in the face of airstrikes and Iraqi army gains.
Yeah it sounds like a lot of their military advisors are being picked off which can only be a good thing.
My main worry is that when the organisation is lost you're going to end up with panic amongst their ranks which will form into anarchy and a lot more random horrific acts in the western world.