Rav Yaakov Hillel, known as one of the greatest (real) mekubalim of the generation said the following: “One has to understand that when the sifrei kaballa talk about hair and beards and fingernails the hair is not hair and the beard is not a beard. If you think that it is, of course it makes no sense!” (From a collection of drashos he gave in America)
My guess would be that this is even more true of words like “world” and “star” which even everyday language uses metaphorically.
Derech: A chariot of fire is a chariot of fire is a chariot where the wheels have legs and bodies that are not exactly wheel-like at all (the merkava). Does it make any difference in hashkafa, halacha, or anything else what the chariot looked like?