I would say that the criticism of ‘identity politics’ is typically that it is used to cover for a lack of progressive policy. Clinton, for example, only supported a $12 minimum wage instead of fighting for $15, and only wanted to move marijuana to Schedule II, instead of descheduling it.
Being represented is important for any kind of group. But being represented is more about policy than the people that implement it, although that is also important. For a clear example, PoC would be better represented by Bernie Sanders than Ben Carson despite Carson being a PoC.