I think the point is that selling a medical device that also requires you to use that vendors mobile device or lose access to them is just a little scummy. My motivation to keep using an iPhone shouldn't be that I'd need to buy new hearing aids if I left. Apple knows how this works, they don't deserve the benefit of the doubt.
A set of airpods + the Minimum Viable iPhone to configure the them to work as hearing aids is way cheaper than standalone hearing aids. Regulatory fetishism around "medical devices" is exactly what enabled hearing aids to become a racket and to remain one long after the relevant electronics became a mass-produced consumer product.
