Strange Disclaimer

I finished Neal Stephenson's The System of the World earlier today. It's the third volume in his enormously long Baroque Cycle, a work of historical fiction featuring such characters as William of Orange, Isaac Newton, the Duke of Marlborough, and King Louis XIV of France. I liked it so much that after reading several thousand pages of book proper I read through the acknowledgments and kept flipping all the way to a disclaimer page where I read (per usual):

This book is a work of fiction. The characters, incidents, and dialogue are drawn from the author's imagination and are not to be construed as real. Any resemblance to actual events or persons, living or dead, is entirely coincidental.

What kind of society includes this boilerplate with ever book? The disclaimer comes, after all, right after several pages of acknowledgments in which Stephenson talks about which historians' work influenced his portrayals of these historical events and historical characters. It is a work of fiction, but it's clearly not the case that any resemblance between the "Isaac Newton" character and the actual person, Isaac Newton, is a coincidence. Why lie like that? It's a heck of a world.