Seems like it depends if you are shooting large hogs, bears, or going to Alaska to shoot really big game. For deer, Graps brought up a great point above. That point has been discussed six times per year since I have been on this forum and the answers are always based on set up, shot placement, and personal preference.
For me,unfortunately, most of my shooting is paper or foam targets nowdays, so about anything that is comfortable is my pick for draw weight, but If I were to go out of state, hire a guide and go after moose, I would probably want to work on shooting a bow 55 to 65 lb at my draw length, and somehow, I would be determined to find the money or means to get one. However, that bow would sit around a lot and just collect dust after the trip. Many bows now for sale 55 lb or greater so I would say more people are shooting weights greater than your mentioned 50 lb than not. Before I would go after something big and dangerous, whether its buffalo or grizzly bear, I would get a bow with as much draw weight as I could handle and have a guide with some backup. For most deer, the majority of experienced people have concluded in similar discussions that about anything that people shoot daily will work with good shot placement.