OS Assistant Platform Lock‑In

When an operating‑system vendor adopts or endorses a specific foundation model for its built‑in assistant (e.g., Apple choosing Gemini), the assistant becomes both an interface and a distribution/monetization hub that increases switching costs, consolidates data access, and shapes which third‑party services succeed. This dynamic raises antitrust, privacy, and interoperability questions because the OS vendor controls defaults and can gate assistant integrations. — If major OS makers formally anchor assistants on a small set of external models, policy fights over platform power, data residency, and consumer choice will become central to tech regulation and national‑security planning.