https://www.cnet.com/news/lg-confirms-full-hdmi-2-1-support-in-2019-tvs/

For its part LG's rival Samsung told CNET it would also support HDMI 2.1 in its 2019 TVs, but wouldn't provide further details -- such as whether it would support the full spec, as LG claims, or just certain parts of it -- by press time. 

For current and even near-future 4K TVs, HDMI 2.1 isn't a big deal, and the current HDMI 2.0 connections are plenty. They handle 4K resolution at frame rates up to 60 per second, and even some varieties of 8K (24 and 30 fps). They also don't require new HDMI cables.