Trump used Crowley’s story to promote slashing regulations at the FDA so that patients such as herself won’t have to suffer needlessly as groundbreaking treatments languish in regulatory limbo. But as effective as the anecdote may have been, the president’s drug regulation-busting agenda will elicit plenty of controversy (and create some strange bedfellows) in the pharmaceutical industry.

Crowley, as Trump explained, has Pompe disease—a degenerative, genetic movement disorder that often kills its host. But she’s survived into her 20s thanks to a novel enzyme-replacement therapy that her father, John Crowley, helped develop by founding his own biotech. (Crowley’s story was also enshrined on the silver screen in the Brendan Fraser and Harrison Ford-led drama Extraordinary Measures.)

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“If we slash the restraints, not just at the FDA but across our government, then we will be blessed with far more miracles just like Megan,” said Trump. It was an earnest and emotional plea that’s hard to dismiss outright. The specter of faceless government bureaucrats and scientists standing in the way of experimental treatments that just might help save someone’s kid from excruciating suffering isn’t anyone’s idea of a winning team.

Yet, the issue is a lot more complicated than that. And it’s already created odd alliances between patient advocates, drug makers, and the scientific community.

On one side, you have people like Megan’s father, John Crowley, who’s currently CEO of the biotech firm Amicus Therapeutics. Crowley’s support for rapid drug approvals (especially for rare diseases) is understandable given his heart-wrenching personal experience with a loved one. But there’s a notable business incentive here, too—Amicus is developing a number of rare disease drugs but has faced multiple setbacks at the FDA, which has requested more trials to prove the treatments’ efficacy. (Since Trump’s speech, Amicus shares have soared more than 18%.)

On the other side, you have scientists and biopharma executives who argue that speeding treatments to the market will actually harm sales and patients’ access to these drugs. “People often argue that the FDA is too restrictive,” said Roger Perlmutter, R&D chief at pharma giant Merck, in a recent interview with Reuters. “We have the sense that the balance is pretty right … you have to have a well-characterized risk/benefit profile.” Other pharmaceutical executives have echoed these concerns.

Why? If insurance companies and benefits managers don’t trust that a drug is effective because it’s been rushed through the regulatory process, or won an approval on the back of a well-orchestrated PR campaign, they have little incentive to actually cover and reimburse those treatments. (There’s also the fact that a massive number of therapies never even make it past early clinical stages because dangerous side effects that weren’t evident in smaller trials prop up later in the development process.)

That’s a lesson that Sarepta Therapeutics, which won a controversial but pioneering FDA green light for another rare disease called Duchenne muscular dystrophy last year, has had to grapple with. The firm announced on Tuesday that it expected sales of the treatment to fall well below analyst expectations in 2017, in part thanks to a revolt from insurers who aren’t convinced that the $300,000 therapy is actually all that effective.

Trump has toyed with the notion of nominating an FDA commissioner who will take a hatchet to the agency’s regulations and essentially allow patients (and the market) to decide whether or not an approved drug is worth it, as long as it’s safe. The families of patients with devastating illnesses may understandably cheer that. But others in the life sciences community worry that such a massive change could tarnish the FDA’s reputation as one of the most prudent and science-driven regulatory bodies in the world.