Continuing the justified, if cynical take, in the near-term I'd worry less about privacy, and more about ads. Microsoft has a track record of putting overt and covert advertising directly into the OS. With deep system-wide integration and awareness of commercial applications, how long it'll take before Windows Copilot turns into a sneaky salesman, preferentially suggesting commercial tools and solutions of the highest bidders, while Microsoft gulps up a firehose of money coming from approximately every company of the planet paying to slot themselves into model fine-tuning?