Doing airdrop is not a total waste of time as we see it. Some Airdrops worth doing. XLM was airdrop ING through keybase that was profitable, Origin protocol did airdrop as well and other projects.
A lot of valuable airdrops are from big projects, recently I've seen Solana airdrops, they have huge airdrop budgets. And each participant received $ 30, which is really a great airdrop this year