I'm not sure why we're putting "lossless" in quotes or defining it in terms of bitrate. Lossless is a factor of compression and conversion; if data is lost in that process, it's not lossless; if it's preserved, it is. Something is either lossless or it isn't, it isn't a matter of being "called" so. The repeated conversions required to play over wired with APM (digital to analog, then analog to digital, then digital to analog again) results in some data loss, therefore it isn't lossless. That doesn't mean it won't sound good and that the APM aren't capable of playing 24/48, but any higher resolution than 24/48 will be down-converted, and it isn't a lossless signal. CD quality is lossless if isn't compressed or converted in a way that results in data loss.
It sounds like the difference between these headphones and the current APM is that with USB-C, Beats will support lossless with its on-board DAC (digital from the source, then conversion to analog with the headphones)--one conversion as opposed to going through multiple conversions as APM does, so Beats will retain a lossless signal and APM won't. And the Beats also support a 3.5mm connection, in which case lossless is determined by the source and not the Beats themselves. That's something APM doesn't support and I wish it did, because that allows me to use them like any regular pair of headphones.
Can anyone actually hear the difference between the very minor "lossyness" of APM's wired connection and true lossless? I doubt it. Sound quality depends much more on the source and the quality of the headphones than whether something is truly lossless or not. But it would be nice if the next generation of APM allows a 3.5mm connection and lossless through USB-C as the Beats do. I'd be surprised if they didn't.