I'm not sure why you think people don't realize this.

It is well-established tradition for both news organizations to call races and the apparent loser to concede, well in advance of December 14th.

Biden's lead in both the electoral votes and the state margins means that in order for Trump to win, he would need to flip multiple states. Recounts typically only move a few hundred votes, and his legal challenges haven't seen any traction.

So yes, it's technically not over yet, but it is incredibly unlikely to have any other outcome.