Well I don't know about any tech which reduces glare of oncoming cars. But in case it hits you, just focus on the left side of the road where the edge is to quickly regain vision. And you should use high/low beam as conditions mandate (Periodically flash high-beam when a shadow-region is developed, keep in low mode other times since it helps you spot sleeping obstacles (Eg potholes) and high mode lets you spot things that are walking/riding/driving on the road (Mostly without reflectors and/or lights) and when on high speeds on the highway or fast roads, keep in high mode when there is no oncoming vehicle because you need to spot it from more far away. Also, do not turn on your foglamps when there is not situation of poor visibility. It's against the law AND it further glares the oncoming drivers. However, you may use them if your lights create a shadow zone.) and always low beam when there is oncoming traffic. Flash lights once or twice to let the offending driver know what he is doing. BMW developed a tech which is really effective. It adjusts and turns off the lights in the favor of the oncoming driver. But not all of us drive around in BMWs, right?
EDIT: About headlight leveling device, it is used to point the low-beam to the correct spot when your car is loaded. The weight at the rear makes the lights focus skyward. But for us, it can also be used to adjust focus. regardless of load.