That's why I only race the White runs properly. I was never a big fan of producers' cheating content just by making tracks reversible. They could have at least change the time of day as someone mentioned, like they did in WO1.
There's not even one track where the Black run is actually better (maybe Amphi due to its White version's poor trying to recreate the Gare d'Europe jump, which feels a bit pathetic to me). Now go figure.