We have diverse view on the validity of airdrop. I personally believe that airdrop is a good start for someone coming into the cryptocurrency space. It gives one the opportunity to learn from the scratch and experience the effort it takes to earn from this space. It may serve as a deterrent for greed as the cryptocurrency space is not a get rich quick scheme.
I think Airdrop does not provide useful lessons to people who have just come to crypto because everyone who joins Airdrop doesn't care about the development of the project, they only think of "when distribution" even they won't know what the project's goals are