Decades of confounding experiments have physicists considering a startling possibility: The universe might not make sense.
What the author means by "not making sense" is the existence of fine-tuning, not explained by over-arching theory.
She asserts that this supports the multiverse hypothesis. If fine tuning is apparent, there must be an enormous number of universes, so randomness can permit our existence.
There is of course another explanation for fine tuning, which doesn't presuppose an infinity of universes.
But that's not "scientific", unlike an infinity of undetectable universes.