But that's an entirely subjective complaint you have there. From my equally subjective perspective, I think Chang Hon varies the most by far from Japanese karate in things like blocking chambers and sine wave execution compared to KKW TKD or Chung Do Kwan TKD. When I decided to recommit towards growing in TKD after years in karate, I actually ruled out ITF-type instructors precisely because the sine wave was too different for me to accept.
Unless you come up with an accepted scoring rubric based on research models to evaluate the degree of departure Chang Hon TKD has from Shotokan karate, you're just being opinionated. Which is fine and all, but it's about as relevant as me not liking the ITF uniforms aesthetically or the flavor of Rocky Road ice cream for that matter.
Sine Wave was implemented about 25 years into Taekwon-Do. It was not part of the original system promoted. I don't think it's subjective that Chang Hon-TKD lifted it's handtechniques from Karate and tweaked the coloured Katas from Shotokan. Pretty damning evidence.