I agree with the other Assassins creed games. At least with Odyssey, that’s what I played most. You can explore all of ancient Greece and there are lots of really good and fun side quests. Just don’t think of it as a pure stealth game, like the first game was, more like an action adventure with stealth elements, or you might be a bit disappointed.
I don’t know the video you are talking about, but the piece of clothing this hats developed from is called gugel. Someone decided to wear the part for the face on the head, and fancy fashion it became.