Essendon were still in the finals race going into that match. If they'd won they would've been out of the finals only percentage behind Adelaide.
Mathematically yes, but it involved a bunch of unrealistic results like Essendon going to Perth and beating the reigning premiers, or Saints losing to last placed Richmond, or making up the 20% gap between themselves and Adelaide. Even as a fantasy believing teenager I remember knowing there was no realistic chance.
But writing this did remind me that Richmond were 6 points clear in dead last at the time of the game. So still an incredible turnout.