Its true, also theres another great airdrop like Stellar, Origin, Safepal, and many else which exist. For UNI i think only active user who receive it, because i didnt participate on it.
Those who used their trading platform for a certain period of time are the ones who got their free UNI. Only one airdrop that I participated is the MNEB airdrop 9https://bsc.minereum.com/web3) . But you can only mine MNEB if you upgrade your genesis address to level 2 or 3, and you can only sell the mined MNEB if you upgrade to level 3, which you will incur about 0.45 BNB to upgrade to level 3. Not an airdrop per se but if you want potential source of passive income, you can avail this even if you say you need to cash out first.