My guess on why this is happening is that the hardware in the TV simply is to weak to support the processing of full resolution 4K at 120hz, this is probably also the reason for not being able to support VRR. They probably expected to be able to do this with the hardware they had or there were some internal miscommunication and when they tried to actually implement it now that XSX and PS5 and RTX 3000 has launched they simply couldn't pull it of with the chipsets in these models.
That seems to be a common theme. I think what started the whole issue was:
PKG6.04960 is the firmware listed with the supposed features (ALLM/VRR) and that is available now (has been since November). If you look at applicable models it is compatible with all expected TV's except specifically the XH900/X90CH series but is compatible with the XH905 series
I don't believe anyone has tried 6.4960 on their XH900/X90CH as they don't want to risk bricking it, plus it doesn't actually specify VRR/ALLM in the feature notes if you read them. This is where people have tried to pin Sony CS down and get an answer, and since no one can and with the features are being removed from certain spec sheets it has alarm bells ringing. I'm still in the 90 day period with mine, but I'm considering what to do.
No doubt it's still a great TV, but a lot of people bought it on the premise of features that were coming as well. And the price range. Imagine if this sentence was removed from the
official PlayStation FAQ for example:
To temper this, the firmware always had a date of Spring 2021 for the XH9000 but as you can see from the notes, it is missing the features. I'm not sure if all those TVs have the 'new X1' chipset . To be clear 120Hz is not an issue to me, but VRR and ALLM definitely were features that affected my purchase. It also affected people considering the XH950 as it has a better panel but not the 2.1 features. As
Bo_Hazem
says, these features were not scheduled to 'drop' before Spring but with the transcripts of imcompatbility and the fact most of us will be outside the 90 day window in Spring, then we need a satetement from Sony specifically about this issue imo.
Windows central also covering it now:
https://www.windowscentral.com/sony-scrubs-vrr-and-allm-upgrade-x900h-x90h-tv-support-pages?amp
And customer service now seem to be singing from the same hymn sheet (of course it's Reddit so take it with a pinch of salt) but there seems to be compatibiity issues with VRR/ALLM and this model):