Here comes HDMI 2.1a, another confusing new spec for consumers

The HDMI Forum has announced its latest revision to the HDMI specification stack, HDMI 2.1a, which promises to add yet another confusing new spec for consumers.
Apple’s new MacBook Pro models offer HDMI 2.0, not HDMI 2.1
Chaim Gartenberg for The Verge:HDMI 2.1a is an upcoming revision to the HDMI 2.1 stack and adds a major new feature, Source-Based Tone Mapping, or SBTM. SBTM is a new HDR feature that offloads some of the HDR tone mapping to the content source (like your computer or set-to