The AMD marketing slogan "the fasted AMD gaming graphics card ever developed" (which by the way, is the dumbest possible slogan, if they wouldn't have been the fastest AMD gaming cards ever developed, what would have been the point anyway??) indicates, that AMD is themselves not sure if the can call their cards the fastest gaming cards ever developed. Even so, they presentation kinda left me impressed in regards to rasterization performance. But it also left me with a lot of question marks in regard to Ray Tracing, DLSS competition etc. AMD avoided to show any real numbers in this department, what makes me guess, that they can't compete with Ampere cards in Raytracing games, especially if used in combination of DLSS. Leaks show that they about on the level of a RTX 2080Ti when it comes to Raytracing. And no DLSS alternative at this point.
So, no, the RTX 3090 is not dead, but maybe slightly too expensive. But not worth it if you don't plan to use any raytracing.
Also, its rumored that we are getting a RTX 3070Ti (GA102-150, 7424 Cuda Cores, 10 GB G6X 320bit), and a RTX 3080 Ti (GA102-250, 9984 Cuda Cores, 12 GB G6X 384bit) rather soon. This will be for part to better compete with AMD and in part of the fact that they probably have a lot of chips which should have become RTX 3090, but missing a few cores, but are still better than RTX 3080 chips (same with the chips for the RTX 3070). I don't think they actually yield a lot fo RTX 3090 chips right now.
My guess would be that we would get the RTX 3080Ti for somewhere $900 to 950. and the RTX 3070Ti for $550.
Either way, in the end of the day Nvidia and AMD are now on very similar performance levels and that means: COMPETITION IS BACK.....AND this is a GOOD thing for all of us!!!! Right now you can't really go wrong either way....