The term was tossed about a lot in connection with the 2016 elections. It was often used by pundits to distinguish Hillary Clinton's pitch that emphasized civil rights for women and minorities from Bernie Sanders' emphasis on economic issues. while this wasn't entirely off-base, "identity politics" still carries a pejorative connotation. Especially among Republicans. Which is why some Democrats take care to emphasize that Trumpism is very much white identity politics. Dibgy Parton recently wrote, "This is the fundamental contour of American politics. When the two parties take opposite positions on slavery, now racial equality, we are divided. It's hard to believe that we are back to this place, but we are. And we can try to ascribe that to other motives all we want, it won't change anything." (It's white supremacy, people. It's always been white supremacy. Hullabaloo 02/04/2018)
But whatever term we use for it, it has become common in the internal arguments within the Democratic Party for the corporate Democrats to try to accuse progressives of being deficient in their concern for women's and minority rights. On the face of it, this doesn't make much sense, since the Sanders wing of the party is very much in favor of women's rights, including abortion rights, and of protecting minority civil rights, including affirmative action. The key difference is that the Democratic progressives also support New Deal economic policies, while the corporate Democrats are on board with the neoliberal economic agenda which is mostly in agreement with Republican positions.
After the 2008 and 2016 primary campaigns, it is now pretty much standard practice, at least at that level, for female candidates to try to portray male opponents and minority candidates to portray theirs as anti-black, anti-Latino, etc. In some cases, it's more objectively accurate than in others. But politics is politics. It's part of the mix. Whether it's effective or not depends on a lot of variables, including who is making the criticisms and, obviously, how the target audiences process the attacks.
I've expressed concern before about the Gillibrand Standard applied in the defenestration of Al Franken by his fellow Democratic Senators in 2017. I'm worried that the lessons Republicans have taken from it is to prepare to deluge Democratic candidates in October 2018 with frivolous allegations of sexual harassment. (Which doesn't exclude their being able to find some real ones.) See my posts: Kirsten Gillibrand as Presidential candidate 12/12/2017; The Gillibrand Standard Takes Out a Female Candidate? 12/17/17; Two weeks too late 12/19/17
Branko Marcetic writes about the use of "identity" issues against progressives in Only When It Suits Them Jacobin 02/02/2018.
During the primaries, Gloria Steinem and Madeleine Albright appeared to admonish young women for favoring Bernie Sanders over Clinton. Numerous liberal feminist writers insisted on the importance of getting Clinton into the White House, regardless of how centrist she may be. “Not electing a woman, again,” warned Rebecca Traister, would be “much more than symbolic.” In a now-deleted post on David Brock’s Blue Nation Review, Clinton loyalist Peter Daou explained that, “[Sanders’] views notwithstanding,” he was “a white male who has been in Congress for over a quarter century,” making him the “definition of establishment,” while Clinton, solely by being “a woman attempting to break the ultimate gender barrier” was “the definition of anti-establishment.”
This line of attack continued into 2017, when similar claims were used to deflect substantive criticisms of potential presidential candidates. Skeptics of Kamala Harris, Cory Booker, and Deval Patrick — three establishment Democrats floated as 2020 contenders who also happen to be black — were told they were simply motivated by bigotry, to the point where some critics were blithely misidentified as white men. In the words of Briahna Joy Gray, liberal discourse became “a world in which personal identity [is] shorthand for ‘progress’ … and ‘white man’ [is] an epithet.”
Howie Klein of Blue America comments on that article at his Down With Tyranny! blog in an apparently ironically-titled post, My Budding Romance With The DCCC, The Blue Dogs, The New Dems And EMILY's List 02/06/2018. "I like his line of thinking," he writes of Marcedtic's article, "but he wastes it on [Chelsea] Manning and [Paula] Swearengin, one step up from vanity candidates." But Klein also stresses, "The tragedy of all those walking garbage candidates the DCCC--along with the Blue Dogs, New Dems and EMILY's List-- try to pass off as real Democrats is that most of them have-- or had before the DCCC chased them away-- fine progressive candidates. Don't be fooled."
Zaid Jilani calls attention to establishment Dem primary mischief in Democrats Anonymously Target Muslim Candidate, Questioning His Eligibility to Run for Michigan Governor The Intercept 02/01/2018.
Charles Blow also uses the establishment-Dem trope here, somewhat carelessly equating Trump's vote with white working-class voters assumed to be primarily motivated in their voting by white identity issues, "He [Trump] was working-class white America’s rebuff to an erudite black man and a supremely experienced woman. Trump’s defects had been validated. He was loved among those who hate." (my emphasis; Constitutional Crisis in Slow Motion New York Times 02/05/2018)