That might be so currently but you are underestimating the importance of Async Compute.
See the technology isn't only in use by DirectX 12, it's also in use and very much used in stuff like:
1. Physics calculations (similar to PhysX only less impactful on performance)
2. Virtual Reality (it is used A LOT, especially of course in LiquidVR which is, according to the HMD developers vastly superior to nVidia's VR)
3. More effective compute for compute tasks (although less of an example than the others)
4. Many many more.
Async Compute implementation is still in it's infancy and it's possibilities are endless and powerful, not a single developer would voluntarily leave this useless.
In comparison it's like asking a video encoder when using a CPU encoding task (which A LOT still do due to limitations GPUs have) to use a Quad Core i5 instead of a Quad Core i7 with HyperThreading because "It's just hype" and the only thing he'll ask you is "Are you mad?!".
Asynchronous Compute is anything but just Hype, it is the future of use just like HyperThreading (or better named Simultaneous Multi-Threading) for anything that will be multi-threading capable... which all new APIs will be.
I'm not saying it's providing an über benefit RIGHT NOW, but it WILL do so sooner rather than later and ignoring it is a foolish mistake.