I think you are quite right to some extent,  the rate at which airdrops comes out these days are much and most are now becoming a shit, and an attempt to scam people. We just need to be careful when applying for airdrop. Any airdrops that request for your private key numbers or request you to sign with your wallet address before distributing the tokens should be ignore this is nothing than means of scamming. We just need to be vigilant enough to know which airdrop should we go for.