530
People born after 2000 have never seen the cosmic microwave background on their TV set.
(startrek.website)
A "Showerthought" is a simple term used to describe the thoughts that pop into your head while you're doing everyday things like taking a shower, driving, or just daydreaming. A showerthought should offer a unique perspective on an ordinary part of life.
It is entirely possible for people born after 2000 to have grown up with CRTs.
It is, but those late model CRTs often had a lot of digital circuitry that displayed a solid color on channels with nothing on them. Unless there was a much older CRT around, they never would have seen it.
Most of the CRTs are going to be older