Regarding light pollution, IMHO, it is only going to get worse, primarily due to the proliferation of LED lighting.
As LED lighting becomes less expensive, more efficient and is now available for virtually any conventional type of lighting fixture, as old fixtures fail, people are retrofitting them with an LED fixture. Many times it is just a simple replacement of unscrewing the old incandescent and screwing in the new LED lamp.
Then there is this mentality where people are not as prone to religiously turn off their lights when not needed, justifying this action as LED's are so less expensive to operate.
With all the new solar powered LED fixtures, LED lighting is expanding to areas where previously, it was not practical, due to the expense of running underground or overhead wiring for AC powered lights.
Municipalities and businesses are "blindly" switching to LED's for street and signage lighting and in the process, due to the cost savings in energy, are adding more lighting than previously.
LED's are far worse (regarding light pollution) that most every other lighting solution currently on the market. Most LED's emit an astronomical (no pun intended) amount of extremely short wavelength "blue" light. Blue light is far worse due to the way it is scattered in our atmosphere (same reason the sky appears blue) and LED's emit far more than their incandescent (and many other types), counterparts. Even the LED's sold as "Warm" still emit far too much blue light.
If LED lights are to be used outdoors, about the only way to make them "Dark Sky Friendly" is to use a yellow filter and still use a shade or some method to prevent light shining toward the sky and not to go overboard with brightness just because they are less expensive to operate. Oh, and the yellow filter, it does not significantly reduce the overall perception of intensity, typically only 10% or so. Outdoor lighting, when it is absolutely necessary, should emit a color temperature of 3,000K or less. At least any light of that color that is scattered into the sky, can easily be filtered out for many astronomy purposes.
I have worked with light and color all my life in both my professional endeavors and as an avid amateur astronomer and hope that people will wake up, think and research as they replace existing lighting and before they add new lighting. If not, the milky way will disappear and our children's children will never experience what we can here in our wonderful neighborhood..
I have had a great passion in regard to reducing light pollution for many decades. There have been numerous times when we would be at some kind of social event and right in the middle of me expressing my opinions, I would feel a tug on my belt from behind, turning to see Georganne. She would whisper in my ear that if I did not shut up, we would never be invited back again. Well, she is out of range at the moment. However, I will shut up anyway...at least for now