There are still a number of good airdrops out there. But now they are occurring few and far between. Similar to any scheme, it is the early adopters who benefit the most. Back in 2017 and 2018, a lot many of the users benefited from bounty campaigns and airdrops. But then, the number of bounty hunters increased beyond a limit and the reward per hunter went down proportionately.
The only profitable airdrop I remember from 2019 was Miracle Tele (who later turned to be scam). All the other airdrops I can divide into two parts. First - airdrops from projects that probably wont be listed anywhere. Second - exchanges that run airdrops worth of $5-10, in which people need to pass kys aka sell your identity.