As of today, January 29 2019 only ONE publicly available software uses the RT cores
Professional applications take time to implement new features, and then test them and validate them. And then validate them again with NVIDIA drivers on Quadro/Geforce lines. It's just a matter of time. Same thing happened with CUDA acceleration, OpenCL acceleration, and GPU browser acceleration. Things take time to implement. I don't get the obsession to count months after the introduction of a totally new architecture with new features like it's some sort of a sprint race to the finish line. There is no finish line.
Having said that, I'm not sure if the alternative is any better, which is just introduce a more powerful GPU with no real additional functionality.
Perhaps the bubble was bound to pop regardless and they felt that this was their best play.
The situation with the crypto bubble was bound to happen regardless. Pricing Turing competitively means stagnating Pascal sales, which means bigger losses. They needed to move both of them.
I don't see RT situation any different from the T&L situation. In fact RT situation is much better, it's supported directly from DX and Vulkan right out of the gate, and supported by major engines, and quite possibly supported by consoles as well. None of these things were present in the first days of T&L.
Why not just keep selling Pascal and wait until 7nm to add all the extra transistors?
NVIDIA most likely wants to make a bigger bang on 7nm, which means big dies, which means waiting for 7nm to be mature enough, which means waiting till Q4 2019. Which means 15 months without new product on top of the 26 months of the cycle of Pascal. That's too long without a new product.
Since sphere tracing and cone tracing are useable on older hardware as well using these techniques would have the bonus of not needing to worry about backwards compatibility for older PC hardware and such.
Usable at what quality level? can they provide true reflections? Soft PCF shadows? Area Shadows? dynamic GI? proper refractions? Nope. RT is an elegant solution that encompasses everything. See Quake 2 on Vulkan RTX for a proper demonstration of a complete path tracing solution.
I kind of wonder if Nvidia has been tipped off to this being what AMD is doing, and that's why it's decided to abruptly put out cards without specialized RT hardware.
Highly unlikely considering it seems AMD is not even ready with a concept of doing accelerated ray tracing. They don't have an architecture, nor fallback layer drivers, nor anything really. All they do is talk about waiting for the proper circumstances to do RT, which is quite frankly is AMD's way of saying we are not yet ready to do RT. Navi is highly unlikely to support DXR at this point. AMD isn't even teasing it. They wouln't do a Radeon VII without DXR if Navi were to have DXR.