Odysseus' long delay in getting home was because he had offended Poseidon. Of course, there are people today who doubt Poseidon's existence.
Correct, but I'm not talking about the mystical origins of the Illiad and Odysee. I'm thinking that the story hides a lot of historical truth with metaphor and allusions to actions of the gods.
Odysseus would not have been a very welcome guest back in Greece, even if he did come up with the wining strategy -- his solution (trickery) would have run counter to the basic tenets of Greek warfare. The victory, although probably very welcome, would have been tainted because it was not gained through force of arms.
In that situation, it would be easy to see why Odysseus would have wandered for so long: he was persona non grata back in Greece. Exile as punishment was not unknown in the Greek world.