Jacob had noted two positive things about his audience. The first was that, as yet, they had obeyed the commandments. The second was that they had come to “hear the pleasing word of the Lord.” Those two positive comments establish the baseline against which he will now show the reality of their situation. Jacob had noted that they had searched for riches, and now notes that they have obtained them.
Jacob is not against riches. There is nothing in his sermon that suggests that riches are inherently problematic. What is a problem, however, is that “some of you have obtained more abundantly than that of your brethren.” Wealth isn’t the problem, it is the uneven distribution of that wealth.
However, it isn’t even the actual distribution of wealth. It is virtually impossible that all could be precisely equally rich. The problem isn’t the wealth itself, but the human reaction to that wealth. Because there are those who have accumulated more wealth, they consider themselves better than those who have not accumulated that wealth. The sin is that you “persecute your brethren because ye suppose that ye are better than they.” The sin is exalting oneself over another, particularly for something so worldly as wealth.
Perhaps this is a reason that Jacob noted that there were those in the society who had been obedient. For Jacob, the problem is the smaller set of people who assume that they are better than others. While that is probably a smaller number, it is also probably the more powerful in society. Human society tends to empower the rich, even though wealth may not display the type of leadership that social welfare might require.