It’s a petition, not a debate. Who is speaking is absolutely relevant. Tens of thousands of tiny developers with a few million collective users aren’t relevant to Google.
> Appeal to Corporate Omniscience
This is not a logical fallacy. You may be thinking of appeal to improper authority. But in that case the criticism is that we don’t know Google anticipated this. Not what you wrote, which is technically ad hominem, since you conclude adversely based on Google being a corporation.
> ignores the possibility that feedback could be legitimate even if anticipated
No, it does not. It says such a petition brings no new information to the decision makers at Google. If Google (note: this is OP’s hypothesis, not a fact) anticipated small developers complaining. Small developers are complaining. That doesn’t make the complaints wrong. But it would make them practically irrelevant.