Yeah, I'm obviously a huge Kerr fan and think he's underrated because we retroactively treat taking over the 2014 Warriors as some sure thing. I think he definitely belongs in the best current coach discussion, but top 5 All-time is a bit much.
He created a revolutionary offense around his superstar and deserves credit for that vision, starting Draymond, and convincing Steph to handle the ball less and use his gravity and constant movement to exploit defenses. Steph's presence in that offense allows them to play multiple high IQ non-shooters at once--that bolster a top-tier defense--without grinding their offense to a halt.
BUT, without Steph on the court, Kerr's offense has always ranged from pedestrian to downright shitty, even with other world-class shooters on the court.
Steph is the offense. Steph is the culture. Steph is the franchise. Because of that, it's hard to judge Kerr independently, much like Belichick with Brady. It's also more than fair to question their drafting and player development post Draymond, whose draft preceded Kerr.