Let me clarify something... And I can be wrong, but from what I understood... Either the hardware is good enough and nanite works for practical application, or it's not and then it doesn't. The 'scaling down' everyone is talking about means reverting to the old method of rendering. That's what consoles and PCs with HDD have to do. It's not about lessening details at the same resolution. The dynamic resolution of the PS5 was there because the nanite system adapts the resolution based on the amount of triangles being handled. If the GPU cannot handle the amount of triangles, or the SSD cannot throughput the triangles, the resolution will be scaled down to maintain the same level of detail at a lower resolution to keep the specified framerate. That means that if you run the same demo from the HDD, assuming the SSD is 10x faster, you'd run the same demo on 144p (technically 144p is not 10x less pixels, but you get the point I'm trying to make. I'm too lazy to calculate right now).
For everyone speaking about 'less details', take note of that.
All true.
Ok, from the outside of this contest or whatever it is.... From what I've seen about the demo and the comments about 'scaling down' I think that both sides are correct in the crucial details. First, this demo COULD run on an Xbox Series X. Hell, it should be able to run on a base PS4. Yes, there would be some 'scaling down' on other platforms as this was built with the PS5 strengths in mind. BUT, that doesn't mean the same thing for each platform. For a PS4 to run this, the textures and objects would have to be 'scaled down' and would not be 8k as they were in this demo. The resolution would also be scaled down. For a current high end PC or the Xbox Series X, it might be scaled down but in regards to those assets. Maybe the SSD on the XBsX can't stream 8k objects as fast...so maybe they'd use 4k objects. You likely wouldn't be able to tell the difference but there would be some difference there at least technically. THAT is how I understood Epic's comments to be meant.
Look, they design their engine to BE scalable to all platforms they support. But, some platforms have specific strengths. Maybe the XBsX would be 'scaled down' from using 8k to 4k objects but maybe it runs a bit higher resolution? Bottom line, we don't know. We WON'T know about this specific demo either unless I miss my guess. I believe Epic was saying this specific demo was targeting and ONLY FOR the PS5. So I think we'll have to look elsewhere for comparative examples to say 'Aha, bitches! TOLD you the XBsX would do better with THIS!' or 'Aha, bitches! TOLD you the PS5 would do better with THIS!'
Seriously, I think a lot of us are going just a tad bit crazy with all these restrictions from Covid-19.

But, and before someone looks up every post I've ever made here....yes I plan on getting a PS5, but I don't HATE Xbox and I think I've at least pretty consistently said that both are going to make people very happy and that I expect minimal if any difference between the games that come to them, at least technically. That's just what this demo and Epic's statements appear to mean IMHO.