The developer working on integrating network display functionality into GNOME Shell shared short video clip to the GNOME sub-reddit […] the feature adds a “screencast” button to the row of actions in the Quick Settings menu. Clicking this opens a modal picker where the user can select any Miracast or Chromecast compatible displays on the network.
If you’re just going to stream video like this you could use any linux hdmi/wifi capable device connected to your TV. If you want to up that with popular streaming services you throw in a remote controlled browser on the device… which is what I believe a chromecast does under the hood.