AppleTV app on macOS not streaming in 4k

How do I stream my iTunes purchases in 4k on my MacBook Pro M4 Pro? I only receive awful looking 1080p streams with now option for 4k, even though I bought them in 4k. The movies are not downloaded and in the AppleTV app settings I set 4k for streaming quality, but Video > Video Quality only shows FullHD and HD resolution as option. I am on a 1 Gbit/s internet connection.