If you have normal anxiety levels, but little pain you may be able to become cautious enough to avoid getting injured or pushing too hard in races, so the lack of pain could possibly be a benefit in racing and high intensity training sessions. If you have normal pain levels, but little anxiety that might help you avoid overtraining/injury or "choking" in races, but how much of racing success is tied to anxiety, i.e. fear of losing, of not being seen as worthy? Are there really "happy warriors" who aren't anxious when competing?

Multiple athletes that I know or have read about seem to have developed the enhanced ability to push through pain because of life experiences that undoubtedly caused them to feel a lot of anxiety or they have so much anxiety about not meeting expectations that they can endure more pain than most.