Quoting: Affectionate_Side_64
You're entitled to your opinion, but I just really don't understand what would suggest he's not. Almost everything points to him being a top 10 defenseman in the league at this point.
Well let's look at his stats and percentile 5v5 (500+ min dmen)
Expected Goals: 3.7 (94th percentile)
Points: 19 (95th%)
Hits: 36 (53rd%)
Shots Blocked per 60: 4.66 (59th%)
Shot Attempts: 195 (94th%)
Shots: 99 (99th%)
Corsi: 50% (55th%)
On Ice Expected Goals against per 60: 2.95 (7th%)
On Ice Shots Against per 60: 60.45 (34th%)
On Ice High-Danger Shots Against per 60: 3.57 (4th%)
Rebounds Created: 9 (92nd%)
Shooting Talent Above Average: 4.9% (64th%)
Now he is also really good on the PP amd has some minutes on the PK.
His numbers tell of a guy who is elite offensively but not good defensively.
Rounding all of that out, I will admit he is even better than I thought he was.
It will depend on what you want in a defenseman but I think you could have an argument for top 10 in the NHL if you weight goal scoring over goal prevention.