I'm still joining the airdrops occasionally but i choose carefully. I used to join the airdrops without learning whether the project is legit or not. 95% of them are scams indeed but if you find a good airdrops, it could gives you nice profits. So far, i got more than $500 through some airdrops.
We believe most of them aren't scams, devs usualy simply can not fulfill their promises without sufficient community support.
Thanks for correcting me but it doesn't change the fact that many of them are scams. I knew that a very few projects i joined its airdrop had a good vision but due to lack of support, they abandoned the project but most of the failed project caused by scammers. They started project that looks legit at the beginning and ask for donations but ended up runaway with investor's money. That's why i always skip the airdrop that requires donations.