Better synonym for "news threshold"?
Newsworthiness is the nearest synonym I can think of.
The definition of newsworthy is:
(adjective) of sufficient interest to the public or a special audience to warrant press attention or coverage.
Examples:
"I question the newsworthiness of some of the items on today's front page."
"How is it that the Kardashians are newsworthy but the hospital renovation is not?"