Earlier quoted context omitted.
Gimp is nearing 30 years old, and it has been used for at most a handful of animation movies. I think, regarding its usage, that this is more of an outlier, than a main purpose of the software. So I don't think that this example refutes OP's point.
and I think otherwise https://girinstud.io/news/2018/04/zemarmot-main-contributor-...
A good refutal of the for-coders claim would be that it's one of the default image editor most commonly included with major Linux distributions. That's a much larger thing than it being just made for coders.