Does systemic racism exist in the US? Interesting link. I've never disagreed with the likelihood of the prosecutor not handling the case properly (too early in any case). I've only said that the grand jury couldn't reach much of a different conclusion (aside from the fact if they rubber stamped or not).
I'm not sure how the perjury surrounding the warrant would affect the probable cause for 2nd degree murder though. The causality between that and the shooting is pretty tenuous. Acting wantonly requires the defendant to be aware of and consciously disregards a substantial and unjustifiable risk. Presumably, he should then have been aware of the risk of shooting an innocent at the moment he lied in the affidavit. Proving awareness and conscious disregard with respect to that seems impossible due to the remoteness between the two circumstances.
I also think Walker's shot would be a supervening event breaking whatever causal chain you could establish from the perjury.
I think it's important to remember the law is not about justice - it's policy expressed in law. Not every miscarriage of justice can be fixed in the court room. Not until a lot of laws change. And that will be too late for Breonna Taylor.