It's a nice to have and frankly aside from maybe water resistance there's no good reason to remove it. The 3.5mm jack has worked since the dawn of portable music, doesn't require often fickle pairing, and of significant issue to me at least doesn't have the potential for some future DRM scheme when the media companies decide you have to use their special app to play something. It's much the same reason I resisted HDMI for as long as possible.

That said, I do use wireless and probabbly would routinely even if the current phone did have a jack, but I would very much like to have it there just for the option to plug a wire in and attach it wherever I feel like. Wouldn't be the first time an aux port or RCA adapter came in handy.