You do have to go down to the comments but it is an official statement by Nvidia.
"Hi. RTX IO is supported on all GeForce RTX Turing and NVIDIA Ampere-architecture GPUs."
The thing to be aware of is that DirectStorage is not gonna be released until next year so you won't see any RTX IO benefits until then. It is gonna be in beta next year so official release could be either next year or the year after.
Personally I am gonna buy a 3000 series GPU assuming RDNA 2 doesn't have an answer to Raster/RayTracing/DLSS combo since my 1080 doesn't have those either. But your GPU already has those things, just slower but DLSS can make up a lot of ground. Wouldn't be surprised if 2070 Super with DLSS can perform like a 3080 native in a lot of games.
Edit: I will still get a ps5 as well unless the MSRP of the disc version is $600 USD