I would disagree with that actually, no script should be used to get any advantage in the game, including to "move quicker".
The same way you are not supposed to use /sell to get up quicker when you are on the ground, you shouldn't be able to use /eject to leave the car quicker as well to get that advantage.
Both are scripts and can be used to move faster but one is considered bug abuse and the other one is "strategy".
You should either allow every script exploit or restrict all of them, not cherrypick which script is good or bad for our personal gains.
Restricting the eject function to slower speeds, if not at full stop should be the way to go imo.