True lollipopping involved totally removing the bottom 1/3 of the plant growth.
It also involves trimming growth points off that protrude greater than 1" from the stem of the plant.
The concept is usually used in a SOG style operation to form single, solid buds with no lower popcorn bugs. What Dill is doing is pruning, IMO, although I have myself referred to this process and lollipopping.
To truely lollipop, you will end up with one solid head nug that forms along the stalk almost exclusively.
Pruning to increase airflow is HIGHLY suggested. Also, since Dill is growing 15 plants and space will be limited....it is important to remove some of the lower branches that will get no light and not form any dense buds, which will allow the plant to redirect that energy to the massive, pop can sized colas that Dill is famous for