"Fiction for people who are stupid but want to feel smart" is hardly new. I do believe the bar has dropped, however.
I read the Da Vinci Code because I figured it'd be good to know what makes it tick. What makes it tick is it's full of grand scale, Carmen Sandiego-grade mystery, easy-to-digest stereotypes and tropes and a deeply anti-catholic conspiracy theory. Compared to the Left Behind books it's positively intellectual. Compared to Robert Ludlum it's Bulwer Lytton dung.
I find that for people to really get a sense of Dan Brown they just need to read the "prologue" of Angels & Demons:
Physicist Leonardo Vetra smelled burning flesh, and he knew it was his own. He stared up in terror at the dark figure looming over him. "What do you want!"
"La chiave," the raspy voice replied. "The password."
"But…I don't... "
The intruder pressed down again, grinding the white hot object deeper into Vetra's chest. There was the hiss of broiling flesh.
Vetra cried out in agony. "There is no password!" He felt himself drifting toward unconsciousness.
The figure glared. "Ne avevo paura. I was afraid of that."
Vetra fought to keep his senses, but the darkness was closing in. His only solace was in knowing his attacker would never obtain what he had come for. A moment later, however, the figure produced a blade and brought it to Vetra's face. The blade hovered. Carefully. Surgically.
"For the love of God!" Vetra screamed. But it was too late.
And I mean, if you wanted you could keep going:
Langdon sat up in his empty bed and tried to clear his mind. "This…is Robert Langdon." He squinted at his digital clock. It was 5:18 A.M.
"I must see you immediately."
"Who is this?"
"My name is Maximilian Kohler. I'm a Discrete Particle Physicist."
"A what?" Langdon could barely focus. "Are you sure you've got the right Langdon?"
"You're a Professor of Religious Iconology at Harvard University. You've written three books on symbology and... "
"Do you know what time it is?"
"I apologize. I have something you need to see. I can't discuss it on the phone."
A knowing groan escaped Langdon's lips. This had happened before. One of the perils of writing books about religious symbology was the calls from religious zealots who wanted him to confirm their latest sign from God. Last month a stripper from Oklahoma had promised Langdon the best sex of his life if he would fly down and verify the authenticity of a cruciform that had magically appeared on her bed sheets. The Shroud of Tulsa, Langdon had called it.
There are parodists who go their whole lives without coming up with prose that purple. And there are people who go their whole lives not realizing they're reading what most people consider parody.