The truth is trading need plenty of money, if you use small money then expect to have little return and you will need the virtue of Patience to ensure that money grows from the little it is to a bigger amount. But if you want to make real profit then use a bigger amount and you will be satisfied with your returns. Furthermore, people who use smaller money blow their accounts faster than those with big money. People who have big money to trade can short in their capital, but they will always grow it back and move forward.
When we talk of investment, it doesn't look like we have to have huge amount before we can invest because what you are discussing is actually true but only for people that have money. In the process of making wealth what I normally consider is Patience because that is what we should have to get there, Is not that I'm going against or arguing with what you said but to me it seems discouraging to the people that are having interest and don't have money. It is clear that everything in this world start from the scratch because if you ask some of the wealthiest people on earth now they will let you know that they started from the scratch which they never thought of being what they are now but since they started gradually they achieved more.
This have stopped so many people from getting involved in cryptocurrency because they believe is only for rich people which was not, I encourage so many people to buy as little as $10 consecutively and also let them know that it's not going to held in a short time but a long period like 5-10 years.