He is but isn't because he's a giant. High punch output, good variety, and at least a decent chin have gotten him into the top ten, but I don't think it's enough to get him much further. He compensates for his lack of stopping power and defense with his physicality(if he was Povetkin's size he'd be hopeless) and it's worked so far, but anyone with decent workrate and power is going to give him issues. Best guy he could beat is Breazeale probably, and both of them will likely get cleaned out of the top 10 for good when fighters like Hrgovic, Teslenko, and Joyce start stepping up. Being an American heavyweight boxing fan is hard.
It's a shame he and Kownacki won't fight each other. Great style match up. They could call it "Whale wars" or "Blood and Blubber."