[i_cant_speel]

You sort of answered your own question. Yes, there are people who are smart but poor. But they are significantly outnumbered by those who are poor but don't have great financial/investment sense. Since there isn't really a good way to differentiate between the two, you have to choose between letting many people be scammed to enable the few to invest or prevent the few from investing to protect the majority.

[davidajackson]

In your argument, the sum of all wealth for the lower class is what's being optimized for here, which you claim is a good thing. We can prevent the most money loss by restricting movement of capital. I happen to disagree with this but's let's table that and look at an analogy.

Say you take that argument and apply it to education. Poor people are generally less educated. Does that mean we should optimize limited budgeting resources to only teach to the average denominator to maximize total knowledge among lower classes (increasing value among many, just as we did with your previous argument)? This means the needs of many outweigh the ability of a few to move up.

I don't think it makes sense to hold back a few ambitious people for the good of everyone, when those few are not adversely responsible for other people's losses.