What he is doing as a 19 year old is amazing. His goal-scoring ability and instincts are elite and he will prolly be a top-5 goalscoring defender for a long time. Clutch. His poise with the puck under stress is phenomenal (compare with Gudbranson his first 2 years) This year too, his defensive work has significantly improved. So there is alot to like.
But......... there is no way he's a top 3 defensemen in this league yet IMO. 35th in scoring for defensemen, the quarterback of a statistically bad PP. A player like Karlsson, forget about his points, he literally controls the game when he is on the ice. Eks just isn't at that point yet. There's a lot of competition for top-3 in the league.