Obviously, there comes a point where you can have too much of a good thing. Eventually, it becomes wasteful or even harmful.
Nighttime lighting is that way.
We need well-lit streets, security lighting, and parking lot lighting. However, we do not need glare, clutter, confusion, light trespass, light pollution, and energy waste. Excessively bright, numerous, unshielded lights cause all of these things. The amount of light you need depends upon the task. For example, you use low wattage colored bulbs for Christmas tree lights, and perhaps a 60 watt bulb for a porch light.