Can Someone Tell Me What Happened To Rox?

Why is their icon so ugly?

Unfortunately, I cannot answer as that is your opinion. They've had the same icon since Huya Tigers. I don't see much of a matter with a new look for a new team.

Didn't they disband?

The playing roster disbanded completely, all going to other Korean teams and their sub Cry (now Zet) to EDG as their bot lane player.

Or did some other company just copy paste the name once they disbanded?

Mixing both questions above: new team, new look, new logo. I'm just glad they didn't change the prefix tag for Tigers for like the 5th time.

To answer your question about the whole "logo change", apparently they wanted to go with something that the entire team thought was cool much like the original icon with the previous tigers (not changing it between 2015/16 as they instead wanted to change the name to something more fitting). From what I can understand, they settled on that specific icon because one of them didn't just want their team to be good, but "Grreat" (the idea being that the tiger is like tony the tiger from the frosted flakes commercials).