It depends on the speaker and the amplifier. Examples - If you’re using a low powered Class A amp on the speakers, it might be a good idea to use a crossover to create more head room for the amp. Or, if you are using small speakers that don’t go very low, like BBC LS3/5As, an electronic crossover can use the small speakers like midrange/tweeter units and move the crossover point high enough to reduce distortion in the speakers.
With your Wilson speakers, I don’t think either of those cases is applicable, and you can just use the subwoofer to fill in at the bottom.
With your Wilson speakers, I don’t think either of those cases is applicable, and you can just use the subwoofer to fill in at the bottom.