I honestly can't tell if this is satire or not, because what you list that he can't do is exactly what he does best.
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We have an immobile champion that lacks reliable CC, that also has gaps in-between attacks which makes it extremely difficult to finish an enemy.
He has 2 forms of CC on 3 different abilities. A root, a slow that can be used for zoning on Captive Audience, and 4 slows on his ultimate. He also has execution damage on his forth shot, and has way more AD to compensate for his locked attack speed. You can also use his Bouncing Grenade inbetween autos if you need the damage right now.
In team fights, the only thing he can really make use of his ult which can be blocked by an opposing player and rarely kills anyone late game.
He can't make use of massive damage autoattacks with execution damage, an AOE ability that scales off AD, and zoning flowers that do a LOT of damage if they stay on them? The ultimate definitely is underwhelming to tanky targets, so you have to time it well to hit the squishies. Even if you hit the tanks, you get the utility from it still, so it is useful.
he is incredibly fast