I don't think identity politics is really the problem. That's not synonymous with wanting representation. And BLM isn't political. It's just acknowledging that black lives matter. It becomes political when a political party makes a point of not refusing to say it.
They don't have a platform besides what's in the name. Any website with a formal agenda isn't "official" in any sense nor have 99% of people marching for justice read whatever you read. It's just black lives matter. And people engineering reasons to avoid saying it without explicitly saying black lives don't matter.
You have it exactly backwards - I believe black live matter, but I don't believe in the organization BLM and they do have an an organization and an agenda.
It's a kafka trap to name your organization with political goals some obviously positive name, and then declare anyone who does not support your organizations methods or particulars of its agenda as a hater of that positive name.
It's so transparent we're just in an age where being honest is rare, and people will convince themselves obviously untrue things - 'they don't have a platform' but they removed their 'what we believe page' including being against the nuclear family https://nypost.com/2020/09/24/blm-removes-website-language-b... .
It's a weird sort of denial of reality to just insist things don't exist, like an organization (which BLM is) with a formal agenda (which BLM has, even if they tried to obfuscate after being criticized for it's more radical and harmful ideas).
