I can explain more in-depth reasoning, but the most critical point: Apple builds the only platform where developers can construct a single distributable that works on mobile and desktop with standardized, easy access to a local LLM, and a quarter million people buy into this platform every year. The degree to which no one else on the planet is even close to this cannot be understated.
That being said, if people spend all their time interacting with LLMs for nearly everything, which is the direction we seem to be going in, what locks them in the Apple ecosystem?
Linux is good enough, so a slightly better OS is not going to cut it.