> Other languages such as French, Russian, and Spanish also seems to assign genders to objects.

Those languages assign gender to words, I think, not objects. A car in German can be "der Wagen", "die Karre" or "das Auto".

There may be languages that assign genders to objects. Perhaps Dyirbal, which Lakoff refers to in "Women, fire and dangerous things"? I'm not familiar with any such language so I can't say.