This goes back to my first comment about definitions. You are defining "equality of opportunity" as "equality". You basically want a meritocracy in which everyone is treated the same. I was defining "equality of opportunity" as "equity". This means people are treated differently depending on their needs. This is the classic fence example.
You admit "equality of opportunity" isn't practical right now due to existing systemic biases. The people fighting for equity would probably say it isn't practical in any foreseeable future. Maybe some day we will correct for systemic biases against certain races or genders, but odds are there will always be some sort of inherent disadvantage for various people. Physical disabilities are one example. That is where equity comes into play. Forcing an employer to install a ramp for a an employee in a wheelchair isn't being "background blind". They are not being treated equally because extra attention and resources are being devoted to them in comparison to their coworkers. However this unequal treatment is just in order to provide them an equal opportunity to overcome a disadvantage their coworkers never experienced. They would not have "equality in opportunity" without an inequality in how they are treated.
You admit "equality of opportunity" isn't practical right now due to existing systemic biases. The people fighting for equity would probably say it isn't practical in any foreseeable future. Maybe some day we will correct for systemic biases against certain races or genders, but odds are there will always be some sort of inherent disadvantage for various people. Physical disabilities are one example. That is where equity comes into play. Forcing an employer to install a ramp for a an employee in a wheelchair isn't being "background blind". They are not being treated equally because extra attention and resources are being devoted to them in comparison to their coworkers. However this unequal treatment is just in order to provide them an equal opportunity to overcome a disadvantage their coworkers never experienced. They would not have "equality in opportunity" without an inequality in how they are treated.