BN is going to be focused on total shareholder returns from simply a rollup of all of Brookfields assets. Whereas the asset management side of things (BAM) is pretty much directly focusing on growing fee bearing capital and returning earnings to shareholders via a dividend. It does have a much more income focused aspect of it.
That is not to say that BAM could not outperform BN. Dividends are one element of total return, the other being capital appreciation. The combination of these two will give an investor their overall returns.
BAM is going to be a more concentrated play in the asset management side of things whereas Brookfield Corporation is going to give you exposure to utilities (BIP), renewables (BEP), asset management (BAM), Reinsurance, Business services (BBU).
I've attached an image on the Brookfield structure to give you some perspective on what BN is made of.
