Google's game-streaming service Stadia is coming to new LG TVs in late 2021. When it lands, it will support 4K and 5.1 surround sound (assuming you've got a Stadia Pro subscription) and will be available for webOS 6.0 first, with webOS 5.0 support planned later. Additional information from The Verge claims that GeForce Now is also coming to LG TVs at a later date.
Stadia has been slow to roll out to the smart TV space. Google's been frequently criticised for the fact that its own Android TV/Google TV platform doesn't yet have official support (though there's a workaround), and it isn't expected to land until later this year, sometime in the first half of 2021. While Google's first-party platform will still beat LG's webOS to the punch, it won't be by much. LG claims it will be the first TV manufacturer to natively support Stadia — though that probably ignores the fact that if Android TV gets it earlier, that means companies like Sony will actually have it first.
Although specific timing wasn't revealed for either launch, The Verge says that GeForce Now support should land "sometime later."