Not really. Overlay the HD curves. Totally different shape. I'll grant you that the slope could be different due to the C41/ECN-2 difference. But how do you explain that the formation of a different dye would alter the HD curve shape, not overall slope?
Also, if you squint a little, the curve looks kind of similar to Fuji Superia 400 as well. Not a Kodak stock, but original Fuji product. Does that mean this new Kodak film is probably cold-stored leftover rolls of Fuji product that Kodak has cut into 400ft rolls?
Rumors are easy to start & feed. What purpose do they serve?
It may be that the starting point was a C-41 emulsion set that then had CD-3 couplers dispersed into it, or it borrowed other components from the still product line. Or it may simply have started as an attempt to juggle an extant product into something different by playing with the emulsions and undercuts. The relationship to Portra or whatever may be no more than a mood board.
The speed will have been determined by what the streaming services' encoding can handle (Colour Neg over ISO 250-ish tends to show up how poor their bit-rate really is) and that an EV 8 lighting environment will comfortably hold T2.8 (which has become a very common aperture choice). LED generally also has a couple of stops advantage over HMI in terms of equivalent output, which is important if you're running generators to deliver the required amperage, especially at today's fuel costs.
The scanning warning is in large part going to be because after nearly 2 decades of Vision 3, extracting information from the very linear upper reaches of the neg to fix things in post (especially on something time constrained and with maximised numbers of set ups per day like a TV/ streaming show) will have become quite habitual. It won't matter as much for those going fully photochemical because those areas simply aren't really going to be accessed, and the straight line section of the neg is the important bit.
As for cross-over, the curves don't indicate that, but people tend to forget that the teal-and-orange look originated from the cross-over (and trying to correct it back in prints) of one of the 1970's neg stocks (the last ECN one I think, back when there was realistically just one choice of top quality cinema colour neg stock worldwide, at the dizzying speed of 100T) when pushed a stop. And until the 1990s it tends to be forgotten that colour neg in general tended to offer either no casts but not great saturation, or good saturation and a bit of a (hopefully pleasing) colour cast. In the same vein, Kodachrome produces technically terrible rendering of some colours, but some people found it pleasing.
As it is, I think some people are wanting to make wild claims about the origins of the new emulsion so that they can pass it off to the unsuspecting as cheap Portra.
