That is still more a problem of people and tribalism. People have always found a way or something to try to build a perceived tribe or group around. It doesn't have to be religion.
As someone raised in one of the two sects directly descended from and named for Martin Luther. I find a lot in OP's assessment that I agree with. The reason I consider myself separate or even agnostic these days has more to do with the people and their tribalism in the congregations around me. Than it does the teachings themselves.
The sentiment also resonates with me as an anarchist. Even with very diluted power, negative and evil things can still happen locally. But if you want to have wide spread evil and negative impact you need to concentrate that power. Even today, no one can approach the roman church's record. Not the Mormons, not the Jehovah's Witnesses, not even Scientology. All quite terrible in their own right. Though they may catch up. Who knows.
The ability to choose how you worship (or even if) as well as who you associate with are important and vital. It doesn't guarantee your ability to make good choices and associations. But at least you have the choice.
Imagine if the only public square you had access to was enforced and policed by corrupt bigoted conservatives, or ML. No thank you.