Both are the worst. Still, people earning from bounty and Airdrop? Isn't waste of time? I don't think Airdrop even gives you a return of your Internet bills lol. On the other hand, most bounty campaigns are scams. Either they don't pay or rug investors and hunters. Better learn something else and earn like trading and service. Nothing is free in the world. Don't run for free money, work hard and earn.
You're right as most airdrop rewards are worthless but bounty campaigns, they kinda hit or miss. Some bounty campaigns give you a very good reward if they got listed in the exchange or seem like a good project. But the rest are paying just barely enough for your effort.