Why do aurthors of magical realism often use a serious tone

It makes the magical details sound more real and ordinary.

Explanation:

Magical realism was a line of art that developed in Latin American paintings and literature, peaked between the 1960s and 1970s, but took its first steps from 1940. In literature, style emerged as a form of reaction to the repressions made by dictatorships of the time. Magical realism has as one of its main characteristics the mixture between the fantastic world, the magician, with what is real. For this reason, the works were written, usually in a serious tone, because this would make it easier for the magical details to appear more real and common.