Can't say I'm surprised, especially considering how precious little we've actually seen of Starfield at this point (and Redfall but Starfield had an actual release date set). Glad they're taking the time to work more on the game instead of forcing it out and hoping updates will fix it.
The HDMI 2.1 port is for ARC connections (like soundbars and other external audio). The TVs themselves only support 60hz refresh rates, so it doesn't do anything extra for PS5/Xbox Series X/S owners in that regard (120hz is what you need to use HDMI 2.1 for).
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