Launched all the way back in early 2017, YouTube TV somehow didn’t offer 4K content viewing support until just a few days ago. In contrast, this has been a thing on Netflix since 2014 (!!!), although Sling TV (which is far more similar to Google’s streaming TV service) still doesn’t come with a 4K option.
That’s certainly not very restrictive, but on the not so bright side of things, you’ll also need a specific “coupon link” delivered by email to be able to order a gratis Chromecast with Google TV from the company’s official US e-store, and only select YouTube TV users are seemingly getting these emails.
You can only get one complimentary 4K HDR-enabled streaming puck in a white color “per household”, mind you, with pretty much no other strings attached or special requirements as far as we can tell.