You're probably right - there probably is some genetic component to biases, etc. It's environmental as well.
But, if it walks like a duck and quacks like a duck, guess what? It's probably a duck. He's a racist - whether he's a virulent racist or one who just exercises inopportune poor judgment, it doesn't matter. He's a racist and should be off the bench.
He lives in Louisiana and has served on the bench there for 20 years. Racial naivete? That's naive. It doesn't take a rocket scientist, let alone a judge, to figure out that showing up in blackface is racist.
This is res ipsa loquitor. He wouldn't have done this but for the fact that he's a racist - whether a Bobby Byrd Klan type or just a run of the mill, mock black people type - it's all racism.
Furthermore, the charge of "racism" in our society has become so toxic and so reflexive, that my tendency is to give just about anyone the benefit of the doubt.