I’ve never had luck using a wall. I got flashed a few times when my truck was new. When I checked them, they were pointed in the air.
I use a dark, flat street, there’s one conveniently in front of my house. I make sure the top of the beam eventually meets the road, about 200 ft ahead. I’ve never been flashed since and I’m happy with the lowbeam performance. Since I live in a rural area I constantly switch to highbeams when there is no oncoming traffic. Low beams are not intended be all you need. Oh, and I never use the driving lights on highways, lighting up the side of the road 20 feet ahead of you is just a distraction.