I think it is impossible to be a millionaire now just by doing airdrops. Airdrops today cost nothing or if you are lucky just $5. The highest I got so far from an airdrop is $6. Bounty millionaire is possible but for airdrop only it is not.
I agree with your opinion, for now the airdrop is impossible to make someone become a millionaire, the results of the airdrop at this time are very low, most airdrops only yield $ 5, indeed in the past airdrop could have made someone a millionaire, but for now it is very unlikely to happen, now there are so many airdrop scams, this makes many people doubt about airdrop, to get $ 5 from airdrop we have to really choose a good airdrop project