That sounds like what I see with Plex, too. It definitely doesn't get it when the intros are unique. And if there's something later that's the same each show (an explanation of the game show, etc) it'll target it as the intro instead.
It's good most of the time, but not 100%.
ah i see, then they must use a similar process. i wonder how big streaming sites do it. underpaid global south workers who manually tag the intro for every episode, or do the files come pre-tagged by the production. maybe a mix of both.