Great Britain, a "secular" state, really?

"There might be an ambition to understand religion better, but Ruth Turner says that a secular society such as Britain finds this difficult."

It is incredible to read articles, by articulate people, who can - almost - persuade us that what they say is true when it is UTTER bullshit!

The "United" Kingdom has never been a secular state and certainly still isn't: The Queen of England and Empress of Canada and Australia and who-knows-what-else is actually a religious leader. She is the head of the Anglican church. How is that "secular" or did I miss something?!
The Queen of England cannot be a Muslim, nor a Hinduist, nor a Buddhist, and not even, by all means, a Catholic!
In XXIst century European Union, we still have Kings and Queens who segregate people according to their religions! Hello?

Tell me about "secular" Britain...