Maybe light fighters proved effective against Empire behemoths and they had to quickly shit out legions of TIEs to counter them.
/overthinking it
well in theory they presumably should have swarmed enemies. like, vs the Millennium Falcon. Tie fighters should have WRECKED it. With it being completely in capable of dodging their fire, while not capable of actually turning and firing at them, with the same maneuverability. Or larger capital ships as well.
what we actually saw was it just blasting through them like they didn't exist. Even Starwars noobs probably would all agree, TIE fighters are not a threat.
Even storm troopers were depicted better. while, yes, fans of Starwars are well aware of the joke, they always miss. A bunch of rag tag farmers, etc all manage to get away from legions of Storm troopers...
Troopers were still shown to be fairly scary in a number of ways.
A New Hope opening scene. Troopers clearly overwhelm rebel forces. Even when shown to be getting away, the vast majority of time, when Troopers are involved, the heroes are in full flight mode. Meaning, even if the Troopers totally fail at their jobs, we are shown that the heroes are still scared of them.
Hoth is another example. Although its more, the walkers, the Imperial Military is shown to be overwhelmingly dominate.
With Return of the Jedi end star battle, its the Deathstar that wracks up the kills on capital ships. Again, at no point are TIE fighters shown to be effective at anything.
I would argue the special additions just make it worse. As, now you add MORE ships, to further the idea of swarming... but hilariously, as terrible as they were before that 10 ships failed to shoot down the Millennium falcon, 40 ships failing to do so is just downright sad.