Tbh I think this is more to get at AMD. Obviously it'll run like rubbish on the non RTX gpu's and make RTX look good. The next question is why doesn't AMD enable DXR. If they do they look behind as they lack performance, if they don't everyone asks why?
I think this is more them just simply supporting DXR, since DXR really has nothing to do with RTX, so Nvidia basically has to support generic DXR unless they wanna try to black box RTX into every game. Which even when they were trying that kinda behavior with Gameworks, often times developers would go with a "generic" version that was often indistinguishable while performing a lot better the following year in the sequel.
Ray-tracing will improve as developers get used to it and figure out what they can and can't get away with and what tricks to use (like falling back to rasterization and cheating when possible) while trying to get performance up. Well that and I'm sure we'll have more "its more cinematic" moments where developers try to justify their low framerates.
The killer app for ray-tracing are gonna be visually impressive but otherwise simplistic indie style games. Like Geometry Wars or that fireworks puzzle game, and there's been some others. Maybe something that even integrates the rays into gameplay. Which a game like Luigi's Mansion (or Ghostbusters), where to catch the ghosts you activate a strong ray-traced light weapon (where the performance hit would be like a slow-mo feature). There's plenty of other ideas (anything with lasers; I played some mobile game where you'd move blocks on a grid to get a laser to hit a switch or target or something, think of a first person VR version of that, where it'd be like those "escape the room" thing but with laser puzzles - some heist game with laser grids). Wasn't there a game kinda like that that came out in the past several years, Talos Principle or something? And something like Portal.