If you thought the naming scheme for USB ports was confusing, get ready to see the same thing happen to HDMI. According to a report from TFT Central, HDMI 2.0 is being dropped as an official name altogether and will be replaced by HDMI 2.1. We don't know the official reasoning behind this major name change, but it seems like it will foster confusion and create problems for consumers going forward. The DisplayPort vs. HDMI discussion just became a lot more difficult.
Before this news dropped, HDMI 2.1 was originally a full-on upgrade over HDMI 2.0b in terms of resolution and raw bandwidth, with some extra features tacked on. The biggest selling point to HDMI 2.1 was its bandwidth upgrade from 18Gbps on HDMI 2.0b to a whopping 48Gbps with HDMI 2.1. This allows HDMI 2.1 to push resolutions of up to 10k and support high refresh rate 120Hz displays at 4k resolutions without the need for display stream compression (DSC), a lossy algorithm to reduce bandwidth requirements.
The higher resolution support was achievable thanks to HDMI 2.1's use of Fixed Rate Link signaling. According to HDMI.org, that was a necessity achieve higher uncompressed resolutions beyond 4k 60Hz, and it allowed HDMI 2.1 to reach the required 48Gbps of bandwidth to deliver those higher resolutions. This technology is different from the older TMDS (Transition Minimised Differential Signalling) used on older HDMI interfaces, which cannot support anything close to the HDMI 2.1 requirements. But, TMDS is still supported on HDMI 2.1 as a backward compatibility feature.
HDMI 2.1 also added several new features to further improve the revision update, including built-in variable refresh rate (VRR), Auto Low Latency Mode, Display Stream Compression 1.2a, and more.
But now, according to HDMI.org, HDMI 2.1 is getting a major fitment change as it is no longer a successor to HDMI 2.0, but rather HDMI 2.0 will now be called HDMI 2.1. Where are all the features and bandwidth upgrades going from HDMI 2.1?? These will now be optional upgrades to HDMI 2.1, including its main selling point of providing higher resolution support.
In other words, what was once a full upgrade over HDMI 2.0 has now turned into an optional upgrade, with every single feature and benefit of HDMI 2.1 being an optional extra for the "new" HDMI 2.1 standard.
Needless to say, that potentially makes shopping for an HDMI 2.1 display or TV a far more complex and confusing prospect. Assuming most manufacturers switch to using the HDMI 2.1 nomenclature, the only way to tell if something supports the higher bandwidth and extra features of the "artist formerly known as HDMI 2.1" will be to dig around for specs.