Why is it "on TV" but "in the newspaper"?

From my understanding, "on" is used to pair with the objects in which you cannot pierce through or open to look inside these objects. For example, "on TV", "on the street", "I put a napkin on my phone", since you cannot open TV, street, phone to look inside, you use "on".

On the other hand, "in" is used when you can certainly look inside an object. "in the newspaper", "in the kitchen", "I am in the airport", are all correct use of "in". You can open the newspaper to read the content inside it, and you can go inside the kitchen, the airport, hence we use "in" in such cases.

We use ON with television, radio, screens, and electronic media because we think of content as being broadcast on a channel, station, or screen.

We use IN with newspapers, magazines, books, and articles because we think of the information as being contained within a publication.

We say “on TV” because TV is treated like a screen where things appear on the surface, while we say “in the newspaper” because a newspaper is seen as something with pages where information is inside. So, “on TV” is used for broadcasts and screens, and “in the newspaper” is used for printed materials like books, magazines, and newspapers. For example, you watch a show on TV, but you read an article in the newspaper.

custom........maybe a tv is flat.......and a newspaper has some degree of deminsion