I've personally fought a character with higher stats in speed, reflexes, strength, and overall power. The only stat I had an advantage in was durability, and yet I managed to win because I was the more skilled opponent. 

Fighting someone with higher stats forces you to rely on your personal skill rather than who can be more creative at making stuff up. I've also fought writers who've used vagueness to their advantage by pulling out moves and powers that are technically allowed just because of a lack of detail in the CS, yet go completely against the prior intent of the character's powers. 

To my mind, stats are more necessary for beginners so they can focus on building the skill required to avoid abusing the creativity that comes with statless characters.