Yes, older Apple TVs can also be calibrated with your iPhone
Apple's new TV calibration feature, which uses the iPhone's front-facing sensors to sense and tweak the output of the Apple TV, works with the company's older streaming boxes, 9to5Mac reports. The new feature will arrive with tvOS 14.5, which is due to release early next week" for the 2017 Apple TV 4K and 2015 Apple TV HD. Apple says viewers will see much more accurate colors and improved contrast" after calibration.
The calibration feature was announced alongside the new Apple TV 4K. It works by having you hold up the front of your iPhone to your TV, so it can sense how the screen is outputting different colors. If the phone's light sensor sees that color is being outputted inaccurately, the Apple TV can adjust its output to...