The phrase "a declining role" is correct and usable in written English.
It can be used to describe a situation where someone's or something's importance, influence, or function is diminishing over time.
Example: "In recent years, the organization has observed a declining role of traditional media in shaping public opinion."
Alternatives: "a diminishing role" or "a reduced role".
"The contract envisions a declining role for the company," Mr. Nagel said.
He noted that, like him, Mrs. Clinton had been pilloried in coal country for acknowledging that coal mining would have a declining role in a 21st-century economy.
It shows that the US had a declining role in international water programs during the late-20th century, which contributed to limited international awareness of low-income water programs in the US, and limited US awareness of low-income water issues.
Two GPs associated patient decision aids with technological change and a declining role for humans, invoking dystopian images of "virtual GPs" (Table 1 3).
The state plays a significant but declining role in guiding economic activity through macroeconomic plans.
"I don't think Paul has joined the government to help preside over a declining American role in the world," said William Kristol, the conservative editor of The Weekly Standard.
There have been multiple reports of Cruise pushing her to decline roles, including a would-be "Dawson's Creek" reunion (though other stars of that show said no reunion was in the works).
Declining a role in the family business, she worked for a year as a special education teacher dealing with children with Down syndrome and other disabilities at Agua Fria High School in Avondale, Arizona.
Connery made something of a habit of declining plum roles, also saying no to Morpheus in The Matrix.
Kidman shared part of her own self-acceptance story by talking about how she declined a role in a Jane Campion film, "A Girl's Own Story," at 14 because she would have had to kiss a girl.
While Grantham sees demographics playing a role declining U.S. growth rates, he's not suggesting that we boost immigration rates in a mad dash to expand the labor force.
