Many LED lighting units now support dimming via a standardized 10v signal. The light will take AC power in, but also a 10v DC input, which controls the the brightness. I assume 0v or unconnected is on, 10v is max dim. There are proximity/motion detectors that can work with this. I haven't done much looking yet but as I mentioned I'm looking for a sensor that will turn the light on when it's dark, but only maintain full brightness for a couple of hours, after which it will dim to some comfortable, lower level until motion is detected. I think that will be a good compromise.
Yes it's ironic that with power-saving LED lights we seem to end up just putting up more lights.
Bright exterior LED lights have a strange quality to them. On some levels they actually are dimmer than than the older-style lights. But at the same time they often are more glaring from certain directions and distance.
I wonder if anyone has mentioned to these installations how annoying and unnecessary their lights are to their neighbors. Could be no one has brought it up and they don't think about it. But they may be willing to turn more of them off when not in season.