In law, there is no upper age limit, petallus. Anywhere the mother and her child are permitted to be - in this case, the restaurant - breastfeeding is protected.
So few mothers breastfeed beyond toddlerhood, I don't think the issue of whether or not to 'ban' it in older children in public places is ever likely to arise.
The ironic thing is that the two photos showed very clearly that the act of breastfeeding was far more explict with the napkin over the baby! So anyone objecting to breastfeeding would be unlikely to have noticed.
Many other cultures - including those with severe expectations of dress and behaviour - have no problem with breastfeeding in a public place. Which cultures were you thinking of?