I don't disagree, Aero. There is no reason you couldn't stick with gear up as soon as airborne with a before Vr failure. If it fails after Vr, then you already have a small advantage over a V1 failure, and could have the gear retraction as an immediate memory item. But for normal ops, there is plenty of performance to leave the gear down.
The trouble is that it then starts opening multiple scenarios, their identification and procedures, so it's simpler to stick to immediate retraction at all times.. That's the problem with writing SOPs - balancing probabilities and risks.