Never cut, trim, prune......unless you have a very good reason to. You should make the least amount of cuts possible, and if there isn't a really good reason for it.....don't do it. And "so other areas can get more light" is usually not a good reason. Most of the time what that really is is "removing the plant's overall ability to grow by reducing photosynthesis". Old growth, bottom growth, lower fan leaves that aren't getting much light AND blocking branches, or blocking good air flow.......those you can make a case for, but each cut should be judged on an individual basis, and each cut needs a darn good reason.
Sometimes, when I'm really on the fence about a certain fan leaf, I'll compromise. Instead of cutting that fan leaf I'll cut only the large middle blade of the fan leaf and come back to it another day.