This is an astonishingly good answer and rings of the kinds of things I've heard from Ben Shapiro. I will personally go out on a limb and say identify politics are a tool I associate (more strongly) with the left. Whether you agree, I don't know. Still, read on:
Basically, everything.
Identity politics stresses superficialities in terms of what people perceive they are. It is not based on what people think or feel, their needs, their dreams, their future. It is a form of subdividing and separating people who should be working together, and it has done so, especially in the US, so that people are not trying to solve specific problems, but attacking abstract concepts that are by their own nature elastic and imprecise.
So, you separate people between black and white, but you forget that those categories are essentially imaginary. There is no identity (cultural, ethnic, historical) among “black” people. In Africa you have literally thousands of ethnic groups with diverse cultures, legacy and languages. They were all thrown together in the same category by the slave traders, but this is not something we should reasonably be using as a form of discrimination today. What is “black”? Many people who identify as blacks have lots of non-African ancestries, so again they could equally say they were Irish, Dutch, British or Chinese. So it is not a really objective concept that we should be using. (BTW, I have a great-great grandmother who was black, descendant from slaves who lived in the Mexican state of Oaxaca, and the rest of my maternal line is full of Mexican native indians; I don’t “feel” black anymore than I “feel” white or “indian”).
Same happens with other categories. “Hispanic” is a laugh, it conflates people with many diverse European and Latin-American Indian origins, wildly diverse cultures, plus one European country -Spain-.
So with the abstract problems that identity politics purport to confront: “the patriarchy”, “capitalism”, “opression”. These are terms that can be used so loosely that they are frequently abused.
Now, if people that “identify as” black, gay, hispanic, trans, etc. all suffer from bad schools, low wages and high crime rates, they can work together beyond artificial and superficial differences in order to solve their real problems. A neighborhood group working against crime is a group of good people defending their families and each other’s families, and this is objective and important regardless of the “racial” (races don’t exist, but that’s another issue), sexual, gender or other body differences. They go beyond “identity” into “human rights, freedoms and needs”. And there, you also have good people who work and toil and respect each other, and bad people who prey on them. Their identity matters not. This is also valid when working against police violence, sexual harassment, bullying, or whatever. Context and nuances are important, but they should never take front row in the fight for a better, more livable society for all.
Not to put too fine a point on it, identity politics is fascist. It teaches that people must live in an apartheid based on what they are, but are not responsible of. People are expected to act a certain way according to their identity, which is stereotyping of the worst kind. People must be considered according to their values, their kindness, their work, their dreams, not their external appearance or their private joys, as long as they harm no one. Identity politics divides instead of uniting. It looks forward to a world subdivided in ever-shrinking identity groups rather than a world united in ideals such as justice, equality and solidarity. It looks at an individual and judges him/her/it as if their stereotypical appearance determined their intelligence, morals or worth because “all people who look like this think and act alike”. That is hogwash and extremely dangerous.
In the end, identity politics agrees with the worst of those who promote discrimination, instead of struggling against it. I could go on, but I’m afraid I’ve rattled too many chains by now.