Not just the drop. Steve Smith simply has that extra screw lose that made him dangerous. If Cooks spends years (plural) refining HIS game AND plays with his hair on fire like Mel Gibson in Braveheart after they killed his woman all hours of his waking life, then MAYBE he can be in the same paragraph as #89. Right now, I don't see it. Not even close.
You don't have to be half crazy to be small and productive. He's heavier than Desean Jackson who's been productive since he's got in the league. TY Hilton. Randall Cobb. Steve Smith isn't the only small receiver to ever play in the NFL, although his career is on a different level than any I've named because of how long he was able to be as productive as he was.
He doesn't have to be Steve Smith, he just has to a Brandin Cooks, which from all accounts, has been damn good so far.