Hola! You’re correct, in an ideal world, we’d be HDR first. However, as @daniele noted, the workflows to maintain that through the entire production pipeline are challenging at best, and though things are progressing quickly, it will still be years before anyone can truly be HDR first.
This is the reason I stay in the camp of as much can be in the LMT, should be. It should be a creative choice of how “HDR” you actually want your HDR to be, as well as how that translates into SDR for accurate representation in VFX, etc. I understand our options there may reach a limit, and aspects will need to be done in the core OTs… but limiting that I think we all agree upon.
All of this exploration is wonderful, working towards core requirements we cannot live without, vs those that are optional, vs those we know we do not want. There’s a lot of great thoughts here I need to fully catch up on as well, so apologies for possibly missing things but basically, I agree with @sdyer on his scenario proposals and “can” vs “must” being things we have to distinguish.