Consistent, deliberate training and being conscious of form is how runners get faster without destroying their bodies. Then show up to a race and let that ego run wild. Finish strong, high five people and quietly sip your beer.
In the last couple of years I've learned that it's important to really focus on whole body fitness, not just what's necessary for running. Strength and mobility are key.
Running is one of those sports that people tend to think the 1 thing that worked for them is the answer for everyone. It's not that simple. People have hips with different shapes. People have legs of different lengths. People have ankle damage from previous sprains. Good form helps for sure, but if you want to claim that all running issues are related to form - I have a bridge to sell you.
After I first started running and losing some weight, I became enthusiastic about it. Then with the notions of 'more is better' and 'no pain, no gain', I cranked up the mileage and pushed through the pain. But I learned a hard lesson when I tore a calf muscle.
Since then I've learned that form and technique, consistent and gradually harder practice, and getting expert help are necessary to really learn something. Ten years later, and over 18k miles logged, I can say I know how to run.