According to Microsoft "Xbox Series X is able to leverage an innovative HDR reconstruction technique to enhance existing SDR games with no work from developers and no impact to available CPU, GPU or memory resources." The XBOX Series X can not only convert your XBOX ONE games to HDR, it can also convert XBOX360 and even the original XBOX games to HDR as well.
Reshade can already do Ray Tracing using screen space thanks to Pascal Gilcher's Ray Tracing Shader, something as trivial as converting SDR to HDR with peak highlights on objects such as Lights, the Sun, etc shouldn't be impossible as well. It would be so amazing to play PC games that don't support HDR Display output and finally play those games in HDR! Heck, it would be even cooler to play your emulators in HDR as well such as Zelda BOTW on CEMU. Here is an article that talks about SDR to HDR conversion on XBOX Series X
wccftech.com/xbox-series-x-can-add-hdr-s...ed-for-it-in-theory/
Please look into this guys, I know it's definitely possible. PCs are more powerful than consoles, Reshade could do SDR to HDR conversion better than the XBOX Series X! I have the i9 9900K and RTX 2080 Ti.