Some people should realise that the terms 'pink' and 'blue' are much reviled on MN, and at least there was only mild sarcasm, not a full lecture on the harm of excessive gender stereotyping.
And yes, the picture is grey.
And the posters are much more likely to be adults, not (female) children.
Yes, I know all that sounds a bit stroppy.
But really it is better when publishing to a large readership to use unmarked terms, to avoid causing unintended difficulties. Basic consideration, if you think about it.