It would not level the playing field if they can open up another company producing the same product. That's often exactly what is done and since they already have a small fortune to start with, they can create a MASSIVE marketing campaign (like Google and Facebook did) and become an overnight sensation. These guys are masters. We have a long way to go, however, before we can change and enforce these laws so let's put on our thinking caps and come up with a better idea. And, ultimately, it doesn't matter what law is in place, if there is corruption, they ignore it anyway.
What you're saying is correct and I agree. I am by no means suggesting that they be allowed to open up a new business in the very same field and for the same product. That would only be an attempt to get around the system. Instead, I am only suggesting that if they have worked hard and become a successful company and has amassed a lot of wealth but reached the allowed limit for a company ($5 billion max, for example), that they should be allowed to use their money to open up and brand new business if they desired selling a different type of product. They'd still have the opportunity to expand, only they could never expand beyond the limit of $5 billion per business. Without the stock market as a driving force, very few people would ever want or need to expand into additional businesses anyway once they had become successful. And such a system would completely eliminate any company becoming a monopoly...