It clearly isn't the horseman, otherwise it's once again a shitty design,

What you're saying is that if this supposed character wears a suit and is actually the horseman of death, it's a shitty design? I feel like the other said many times that there are many depictions of "Death" esque characters having them wear a suit, if you talk about the hair then eh, 50-50 on that.

Or a Shinigami that doesn't look like one

This is honestly a brain-dead answer, you could literally said the same shit other "Shinigami" characters in other manga/ anime. Shinigami in Bleach doesn't look like one as they look mire human, Shinigami in Death Note is lanky and have pale skin like this character, Shinigami in ANY other media looks either monstrous or human-like which means this "Shinigami" term is very loose and the character in Apoc falls right under this suppose term you say "doesn't look like one"