In answer to one or two questions. Historically, many martial arts have tried to ensure their continuation by becoming a sport once the conflict or social condition that lead to their creation was past. The problem with this is that no one wants to take part in, or watch, a sport in which the contestants die within the first two seconds. Therefore a set of rules have to be introduced to make it safe. Which is a bit like a system of gardening that ensures nothing grows. Inevitably the style will change to match the rules, often becoming unnecessarily complicated when the simple move would hurt/kill the opponent and often becoming simpler as victory begins to depend on fitness and strength rather than technique. If we trained people to take part in tournaments we would have to miss out many of the most effective techniques. It is not uncommon for people to train to a high level in some styles only to find that when they get attacked their skills are of no use, because no one showed them how to win a fight, only how to keep a fight going for minutes without anyone getting hurt. Having said that, occasionally a student will want to take part in a mixed style tournament, but will have to take some time leaning to limit their use of techniques. Invariably they will end up saying,"I could have won in the first seconds if I'd been allowed to do this or that."
Many tournament styles are exciting sports in their right, and often they give physical confidence to that translates into an ability to stay in control in the face of aggression that is enough to enable the participant to deal with it. They need to be careful though as they simply won't be that good against a real martial artist.