1) Crytek is not doing full ray tracing. It is only ray tracing highly reflective surfaces from lower resolution geometry. This leaves out shadows, and also isn't applied to rough materials.
2) Agnostic GPU Acceleration - Yes, but not unique to Crytek. DXR is also GPU agnostic. The RTX ray tracing drivers from NVidia are simply using DXR features on the older hardware. NVidia could implement ray tracing on even older video cards, but it would be slow. - Also note that AMD is working on DXR drivers for their current GPUs, with hardware specific features for ray tracing coming in the next generation, which is the GPU that will appear in the PS5 and XBox 2020.
I think what Crytek are doing is great. Every technique to get ray tracing effects and ways to speed up ray tracing are always a really good thing, as 'realism' in games is not about pixel count, but about lighting.
However, for now, this technology might be limited to gaming, as it cannot do realistic ray tracing. My second concern is they could fragment game development, by not offering the same ray tracing concepts that other real-time technologies all use.
Also, it seems odd that instead of building from DXR and DX12, they instead are building from DX11, which is not as fast or efficient. This is especially strange for a technology like Ray Tracing that needs multi-core to GPU communication that DX11 doesn't do well. Besides, DX11 'only' GPUs are quite old in 2019, and there doesn't seem to be a good reason to target those GPUs for something that is still has a heavy cost on performance.
DXR is a Microsoft technology, but they have helped Vulkan implement nearly all the features, so that developers don't have to lock themselves into Windows. (Which is quite something to see from Microsoft.)