You're confusing wi-fi 6 (which is still 5Ghz) and wi-fi 6e (which uses 6Ghz and the separate radio in your RBRE960). The FireTV 4K Max is only wi-fi 6 and still uses 5Ghz. From it's Amazon product page: " Supports 802.11a/b/g/n/ac/ax (Wi-Fi 6) networks. More @Wikipedia
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