A hajib is nothing more than a scarf worn on a woman's head. One need not be Muslim to do that.
And you'll notice the Queen is wearing that scarf in no different fashion than is this Iranian Muslim woman.
This woman isn't even Muslim. She just thinks she looks cool with a scarf on her head.
Ditto
Women of all ages and religious affiliations have worn scarves on their heads for hundreds, maybe thousands of years.
If one is in Spain, the same thing that's called a hijab in the Arabic speaking world is called a mantilla.
And it's not at all uncommon to find not only Spanish women wearing mantillas, but also French Catholic women.
From what I can tell, the people who have something to say about women wearing headscarves are people who quite simply have never traveled far enough from their provincial hovel to see that women the world over wear scarves on their heads and that for women to do so when visiting a Muslim country is no burden. They need only treat is as yet another fashion accessory and go on about their business. As for the folks who have have something to say about hijabs, y'all really need to get out more.