Well given that financial planning is my job, I think I have some basis for saying it would a terrible decision, at least financially.
I think this is precisely your problem. You are just seeing the financial reasons and dollar signs in this equation. I'm not saying this isn't important but leaving college to play in the NBA deals with more than just money matters. The college game is a completely different animal than the NBA and maybe, just maybe, Russell wants to have another year of the college experience. Once you leave college, you are done for life in that arena and the rest of your playing days is in the NBA. Ya think maybe he might want another year in the college experience and all the positives that come with it? I don't know, but it's his decision and to say it would be dumb not to go to the NBA is quite presumptuous.