HDMI cable purchasing is about to get a whole lot more complicated
Source-based tone mapping will be introduced with HDMI 2.1a during the 2022 Consumer Electronics Show, but between that and the newly redefined HDMI 2.1, it won't make buying cables any easier.

HDMI 2.1a won't make it any easier to buy a cable
The HDMI Forum has announced that HDMI 2.1a will be introduced during CES 2022. The new spec replaces the older HDMI 2.1 spec introduced in 2017, however little will change for customers.
According to The Verge, HDMI 2.1a adds support for source-based tone mapping to devices.
The addition means that an Apple TV or PlayStation 5 will be able to perform HDR tone mapping before sending the data to the television.Offloading processes to the source device could mean reduced lag times, improved picture calibration, and better mixed content mapping.
The HDMI Forum says this update could be added via a firmware update to devices. Hardware manufacturers may wait to introduce the spec in new products.
The HDMI spec isn't the easiest to understand. The HDMI Forum states that manufacturers are not required to adopt new features in order to label products with the latest specs. Earlier in December, the HDMI Forum actually eliminated the HDMI 2.0 spec and placed all devices using HDMI 2.0 as a subset of HDMI 2.1, despite HDMI 2.0 devices like the MacBook Pro not supporting some HDMI 2.1 features.
Manufacturers are asked to clearly label which features a product takes advantage of, but it isn't always clear. Marketing names can often obfuscate the actual capabilities of a cable or port, and identification labels aren't always in use.
Customers will have to be as vigilant to ensure they are getting the right HDMI features when purchasing a TV, monitor, or cable. CES takes place from January 5 through January 8, and AppleInsider will be covering the show as it progresses.
Read on AppleInsider

HDMI 2.1a won't make it any easier to buy a cable
The HDMI Forum has announced that HDMI 2.1a will be introduced during CES 2022. The new spec replaces the older HDMI 2.1 spec introduced in 2017, however little will change for customers.
According to The Verge, HDMI 2.1a adds support for source-based tone mapping to devices.
The addition means that an Apple TV or PlayStation 5 will be able to perform HDR tone mapping before sending the data to the television.Offloading processes to the source device could mean reduced lag times, improved picture calibration, and better mixed content mapping.
The HDMI Forum says this update could be added via a firmware update to devices. Hardware manufacturers may wait to introduce the spec in new products.
The HDMI spec isn't the easiest to understand. The HDMI Forum states that manufacturers are not required to adopt new features in order to label products with the latest specs. Earlier in December, the HDMI Forum actually eliminated the HDMI 2.0 spec and placed all devices using HDMI 2.0 as a subset of HDMI 2.1, despite HDMI 2.0 devices like the MacBook Pro not supporting some HDMI 2.1 features.
Manufacturers are asked to clearly label which features a product takes advantage of, but it isn't always clear. Marketing names can often obfuscate the actual capabilities of a cable or port, and identification labels aren't always in use.
Customers will have to be as vigilant to ensure they are getting the right HDMI features when purchasing a TV, monitor, or cable. CES takes place from January 5 through January 8, and AppleInsider will be covering the show as it progresses.
Read on AppleInsider
Comments
The HDMI forum should replace the people who make decisions. They are useless.
The HDMI cable is the root cause of issues most of the time with the the length, the speed, the version being the culprits. And of course Samsung TVs don't support Dolby Vision but hawks Samsung's proprietary HDR10+ format. Talk about a labyrinth.
…and they wonder why people get confused.
I also use it to put labels on PSUs so I can know what product they're for and their output. Apple's PSUs are easy to remember, but most products are hard to read or generic.
https://www.brother-usa.com/products/ptp300bt
A new high bandwidth cable that isn’t dependent on itself, so it doesn’t matter if you bought it at a thrift store or a high end audio website it acts the same. The bandwidth is future proof to 20 years+ so it can handle anything that’s thrown at it. New features will be dictated by the hardware/software and the cable is just a tube for features. For example PlayStation 6 wants to add 3D images to a TV: done. Apple TV 6 wants to add an exclusive audio standard like Spatial Audio to receivers: done. The cable you bought is irrelevant because the capability is so high from the start.
Can a new “HDMI 3.1a gen 3x Series 2” standard add these features? Sure. But the fact it has the same form-factor adds more chaos to sort through. HDMI needs to end ASAP.
Better if all new devices can detect what is plugged into it. For example you plug in your HDMI cord into your TV and it displays “HDMI 2.1a plugged in...” then the notification slowly fades away. All settings on devices, whether it’s a game console or Apple TV should tell you what cable is plugged in. This is ridiculous.
I wish the test was smart enough to tell me what the capabilities of the cable and overall connection between devices are—in the same vein as how BlackMagic tells you what kind of media capabilities your disk performance is capable of, I wish it would tell me that what the cable is, what my overall connection is, and what features I may not be getting.
https://www.hdtvsupply.com/hdmi-testers.html
Here's 2.1 8K stuff...
https://www.hdtvsupply.com/8k-hdmi-product.html
We're also at the current limit of what affordable active cables can do, which is why these standards aren't moving forward even faster. Timing correction and error correction chips which can operate at higher speeds are enormously more expensive. You want something faster than HDMI 2.1's 48 gigabits? Get ready to pay $350 for a single 1 meter cable.
meanwhile there are a dozen different cable standards for hdmi and displayport bleh