The problem is that many reviewers have to have such a diverse portfolio of titles to invest their time. Often times they don't have the leisure to explore the finer intricacies of a given game.
On a personal note, I tend to confine myself to a smaller range of genres so that I can better voice my thoughts on what makes a given title stand out compared to its contemporaries but that doesn't mean you should listen to me over any other content producer.
