Bluetooth Audio. Manufacturers have failed to pursue an "opt-in" deployment path. If/when they wanted to make the transition, they should have made (the next

Bluetooth Audio. Manufacturers have failed to pursue an "opt-in" deployment path. If/when they wanted to make the transition, they should have made (the next revision of) Bluetooth good enough that users want to use it. Instead, after being present for years and years on phones, they finally decided to force adoption by dropping the headphone jack. Why? Well, there are the "thin" and "no room" arguments (oh, and, "waterproofing" -- really more splash-resisting), but those don't seem convincing of themselves. There's the chance to sell expensive headphones at substantial markup. And, there's however much behind-the-scenes pressure to transition the delivery channel to entirely digital, where DRM can ensure that content is not copied and, as part of a larger push, that all revenues for listening become recurring revenues in perpetuity. (The thing Microsoft's been trying to accomplish with Windows and Office licensing, for years now.)