Something that bugged me about the 2080 launch was the lack of HDMI 2.1 support, I see Samsung TV's with support for 4k 120hz Freesync 2.0 (part of the 2.1 standard) are coming soon, I guess this screws with nvidia's gsync BFG push so no HDMI 2.1 for us.
HDMK 2.1 specs weren't finalized AFAIK, there may be a future driver/firmware update that will bring HDM2.1
HOwever, Freesync is not a requirment for HDMI 2.1, Freesync is an AMD propriety name for their drivers that supports Adaptive sync. Adaptive sync is only optional in HDMI2.1, most TVs wont bother with the extra costs.