Why is the Winmillion so good?

I saw this topic about the Winmillion needing a 5-star version, and everyone were saying that it was already overpowered, should be nerfed, and stuff like that, but I honestly don't get it. I even have the Winmillion. It's the primary weapon for my alternate knight.
Damage-wise it's quite a bit weaker than the Ascended Calibur, even if you hit with its projectile on every hit, which its attack speed makes up for, but that only makes it an average 4-star Normal damage weapon. What in the world makes that "OP"?

Maybe it's because they agree with you, and there's not much more to say. :)

I believe that the person saying the winmillion was overpowered was being sarcastic.
Wqksayi-Alt wrote:
IMO the winmillion needs a nerf not an upgrade
In all seriousness, it probably will not happen in the near future or even far future.
The "In all seriousness" makes me think that before that they were being whimsical.
Winmillion is not powerful by any means, but it is quite fun.
The thread in question is this. If I were you, I would have just continued that thread.
Only one poster in that thread opined that Winmillion is overpowered. My view (and the consensus view, as far as I can tell) is that Winmillion is not overpowered.