Dex Desktop
Wireless DeX relies heavily on Wi-Fi Direct (a technology where your phone and TV talk directly to each other over wireless frequencies), having the TV locked onto a hardwired Ethernet cable often shuts down its wireless "listening" mode entirely.
Now that you've spotted the culprit, the quickest way to get DeX up and running is to jump into your TV's settings and temporarily switch the connection over:
Tv Settings > LAN > Network Settings > Select Wireless
Or
Tv Settings > All Settings > Connections > Network > Network Settings > Select Wireless
Tv Network Settings
Just make sure you connect the TV to the exact same Wi-Fi network as your phone (ideally the 5 GHz band if your router splits them, as it has the high bandwidth needed to keep DeX smooth and lag-free).
Dex Wireless Connection
Once you are done using DeX, switch back to Ethernet cable to get your maximum stable speeds for streaming or gaming.
Thank you. 🙏
