One of the most interesting parts of that gap is the one day battle he fights in against Egypt right after Troy falls where he's captured until seven years later someone shows up who tries to ransom him to Libya.

Why?

Because an event like this really happened.

In the 5th year of Merneptah there's a single day battle between Egypt and allied forces of Libyans and sea peoples, at least one of which is commonly thought to have been pre-Greek (the Ekwesh), and Egypt is successful capturing many prisoners of war.

Exactly seven years later Egypt is overthrown by an usurper Pharoh, with the following dynasty writing that it had been overthrown with the help of outside forces.

While there was likely no 'Odysseus' involved, it's a useful reminder that sometimes there's historical accuracy buried inside mythology.