I personally believe that stories like the Iliad and the Odyssey were more like a performance art. Someone would tell a story, while the audience would come with suggestions "he killed the Cyclops!" "the wine was poisonous!" "they hid among the sheep!", and they would change the story according to the mood of the room. Similar to how DnD works today. If this is true, there can't even be a definitive true original story. This opens up many cans of worms like "who decides the cannon? The author or the audience?".

Nolan's movie is in many ways a good adaptation (it's fun and engaging to modern viewers), while also being a great reflection of current Hollywood (casting, substitution of religious plot for natural plot).

You also can't say "we went to the festival and we were enjoy" which is the form of your bored example earlier. Different verbs work differently in basically every language (even otherwise quite related ones), for no particular reason.

I do agree on the part that if you try to translate as a map of words/expressions/phrases to the other language you'll often run into trouble because either of the languages has more nuance for one concept than the other and you want to try and capture some of that nuance. I'm generally a "no untranslatable words" guy but you do at least have to expand words into several words occasionally, or vice versa sometimes, with good knowledge of the nuance in both languages