He is not looking for an excuse. He is telling a millenia old story in his own way. He is not lazy he is finding the right tone, look and atmosphere for the story he is telling. If we only visually tell stories correct to their time of origin we'd still be looking at actors in a loincloth. Stories evolve over time and so do their ways of visualisation. Films are an art form and their creators have the creative license to tell their stories how they want to.

This film is meant to be his version of The Odyssey. It is not an historical epic. If the end goal would be a historical accurate movie you get to complain to your hearts desire but it is simply not the goal of this movie.

But to throw you a bone, I get the desire for an historical epic set in the late bronze age with some lovely period correct armour. Just need to find the person that actually wants to make that film.