They can and should be pruned, but of course, not this kind of pruning. There are types of pruning that are necessary (rejuvenation pruning, production pruning, etc.), but decorative pruning where you leave just fou leaves is crazy. It’s one thing to remove dry branches, suckers sprouting from the tree itself, and those that cross the center of the tree… so yes, moderate pruning will prevent pests and problems, but as I was saying, such extreme cosmetic pruning will attract many more pests and ruin everything