The phrase "as a mainstream source of" is correct and usable in written English.
It can be used when discussing something that is widely accepted or recognized as a primary provider of information or resources.
Example: "The internet has become recognized as a mainstream source of news and information for many people."
Alternatives: "as a widely accepted source of" or "as a primary source of".
Wind power, recently described by USA Today as "a decidedly mainstream source of energy," provided 10.6% of the electricity Texas required in 2014 and could provide nearly twice as much in a few years, according to Yale Environment 360's contributor Roger Real Drouin.
"If MSNBC wants to be seen as a trusted mainstream source of news and commentary, it needs to end its silence and fire Pat Buchanan".
Fox News is an alleged "mainstream" source of news, yet 59% of their information is false.
Zuckerberg's comment draws a false equivalency between "mainstream sources" of news (including TechCrunch) and political groups masquerading as news brands.
Although Fontaine declined a direct interview, I spoke with his attorney, Mark Bankston, who told me that more than a month after the shooting, even after the photo has been repeatedly debunked, Fontaine continues to be harassed and threatened by an InfoWars audience that has been taught to disregard all mainstream sources of information as "fake news".
Background. "Culturally insular communities" are defined by a religious or ethnic orientation that effectively places them outside mainstream sources of information on health promotion.
Today, solar energy as a mainstream power source remains on the wish list of the state government.
Once a niche financial instrument, sukuk have become a mainstream alternative source of capital for corporations.
To be a rebel you need a society to rebel against, a Man to kick in the nuts, and - as Doherty found - the figure of the drug-taking, hell-raising star isn't so much counter-cultural these days as a vital source of mainstream entertainment.
Trump, he thinks, offered churches — often courted by mainstream Republicans as a source of votes, and then all but ignored — a highway back to cultural prominence.
