A controversial take that probably shouldn't be.... Airdrops should have lockups. 

Hyperpunk. Nouns. OP Citizens House. Co-founder, Scout Game. 
https://scoutgame.xyz

Also, that should have an option to claim to a different wallet as well if user is willing to. Like "Connect the eligible wallet to prove Ownership" and "Claim to a different wallet". Because, people are farming long time for Airdrops, some projects take years. So, there are chances that user compromise their wallet. So having such option will make the users effort as precious.