Some claim it's them covering their ass thanks to the SUE SUE SUE culture of the US. I understand that, but when it's a purely technical decision they could ea

Some claim it's them covering their ass thanks to the SUE SUE SUE culture of the US. I understand that, but when it's a purely technical decision they could easily enough give you constructive feedback. You missed these two edge cases. Your code crashes on certain inputs. This is very inefficient, you could have done XYZ. You could automate chunks of this, and protect yourself from any discrimination lawsuits by just making any engineer who reviews the code have zero knowledge of the candidate.