The Opal C1 webcam is being marketed as a replacement for the built-in Apple webcams, which were limited to 720p for a great many years. The newer MacBook Air, MacBook Pro, and iMac have a 1080p webcam. But the overall visual quality has always been meh.
Apple has to cut corners somewhere to keep their products thinner year after year.
The 4K visual quality of the Opal C1 rivals that of a DSLR camera. Jon Prosser, host of Front Page Tech, replaced his Sony DSLR camera with the Opal C1 for his Genius Bar Podcast. No one noticed the difference between the two.
NOTE: Check out the longer version of this blog post.