I do agree, because most of airdrops are scam. The project sometime scam and do not paying for our job which have promoted their project. I face many times of being scam in airdrop.
First of all we need to decide what means scam, the scan means willingly, on purpose deceive people, in order to get their money stolen. So now, I think, you must agree, the definitely not 99% of air drops are scam.
scam can be identified in many terms. you can get scammed if you pay but you didnt get any return, you can also get scammed by working without getting paid, etc. there are many ways to get scammed and airdrops is not an exeption although i disagree when the op says 99 percent. as on what ive experience as an airdrop enthusiast there were most of them are still paying a long as youv done the small task given by them correctly. i think 70% of the airdrops are legit or paying and the rest 30% does not pay you or they pay thier coins without any future values.