Presumably they are implying that if they read creative suggestions, they open themselves to the possibility of being sued if they ever implemented anything similar to what was suggested. Doesn't sound too complicated to explain to a kid.
It's such a terrible response for someone that was not in fact suggesting a new feature for the franchise.
And even if it had been, rejecting the entire letter for one sentence is still bad.
It's polite. Being polite is pretty much expected here.
It's hard to describe but it almost feels to me like media today - this applies to games and films and everything - is often created at a meta level, a simulacrum of the real thing. Like in the 80s and 90s people were trying to make things that were fun and interesting and probably based on their life experiences. And now they're trying to make things that are the best distillation of whatever was most successful before. But that makes it feel dishonest, corporate.
Even Microsoft in the 90s could still make stuff that felt fun and unique. There was a counterpart to Creative Writer called Fine Artist that was equally good.
I've let her play around with Google Docs before. But what I really wanted was something like Creative Writer that is more kid friendly. I used Gemini (sorry) to suggest some software and it suggested "Book Creator" which is intended for schools/teachers. I signed up as a fake teacher and added my kids as students and they did create some really creative books, importing images, and adding their own drawings. But it's still missing that kid-friendly vibe like Creative Writer.