YANBU
It's missing the point to say that it's just a pic in an Argos catalogue.
It's a reflection of gendering of children at an ever younger age.
Now, it seems that quite a lot of posters are just fine with reinforcing gender stereotypes.
But even if you do think that, is it really OK to have one set in pink? Why?
The slew of objects, which in ordinary life are not pink, being pimked up for little girls is a very recent thing. And is presumably to get people to buy twice. If you look at catalogues from a decade or two ago, it simply wasn't the barrage of stereotypes and colour coding that it is now.