The goal is consistency
Tapping the measure to "settle" the powder may allow a few more bits of powder to be added, since bp is measured by volume. However, the tiny amount you would add isn't really a significant amount compared to the whole charge.
You are right to try to achieve consistency, for that is the important goal. If you load the same way every time then you will obtain more consistent, trustworthy results and have more confidence in your guns and shooting ability.
Whether you tap the measure or shake it or just pour it in isn't really as important as doing it the same way every time. What's probably more important is that you also compress the load with the same force each time you load. Compression is important to getting a homogeneous charge and thus even, predictable burning through the charge.
Establish a routine and don't change without good reason, and if you do need to change, stay with the change for a long time also.