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
There's nothing left to anyone who's hoping for a good airdrop as most if not all of them are just trash can only bring dust value, there's no longer a good space for airdrops to be enjoyable but if you have some faith or you still wanted to proceed just don't expect too much and allow those trash to stay inside your wallets and cross fingers that it will bring something nice once those airdrops get the chance to be listed inside exchange and bring good value.