Anyone can trade wether you're rich or poor. For me, there is no difference between them but their trading capital. Why? Because they can both become profitable or not profitable in trading. They both need to do backtest or do a demo account. Rich traders don't trade with the same margin as poor traders, they put margin based on what they can afford to lose. The only difference I see in them is their trading knowledge and mindset.
Trading knowledge of a rich person and a poor person can't be equal, because there will be many ways through which the rich trader may pass and he may faces different problems but the poor trader in these ways didn't worked because he didn't have fund at some place. Therefore the rich trader I think will be more knowledge about the trading. And knowledge in the trading has different benefits which can only understandable if there is a situation came in which loss is near.
By gaining much experience puts a person in some safe zone, he knows how to work in which place at trading. He have the ability to get more profit by investing just a small amount many times.