Your posts contain at least two claims, actually. Yes claims, not facts.
First, that most of the short-hair Sasha art derives from the specific angsty headcanon "created" by some one artist. Second, that the artist in question is actually the one who started this headcanon, or so they say.
I took issue with the first claim specifically and questioned it's validity. You instead clearly tried to support the second claim, either because you're the one who misread the posts you're replying to, or because you believe that if the second claim is true it automatically assumes the first one is true as well, in which case how would you explain all the short hair sasha art that had nothing to do with that headcanon and that existed even before the TC was first leaked aka the episode AFTER which the angsty headcanon became popular according to you and people in your image?
Either way, you still haven't addressed the original point. And even the second claim isn't as solid as it looks cause your proof is asking to take one person words on it. But I'm less interested in that.