Can you think of any other timed event in which a person who runs out of time gets a draw?
If it's impossible to mate the opponent, a player should not get a win, regardless of their opponent running out of time.
How that is implemented, depends on the organization. In the case of chess.com, only the material the side with time has is looked at, with one exception, to determine if there sufficient material
Can you think of any other timed event in which a person who runs out of time gets a draw?