...Best suggestion I can give is interact with dapps/protocols where you feel like doing so and leave rest.
In this case, the chance of receiving airdrop will be approaching zero. Only when interact with a large number of contracts will you have a real opportunity to receive a reward. And the amount of this reward will also depend on other factors that currently can only be known to the project team.
Maybe he shouldn't give up yet because there are some other few airdrops one can also hunt for because the good projects upcoming make use of this distribution through airdrops to get their project and coin more recognizable to an extent that it receives the target on public attention and attractions, which means there are still some few ongoing and most rewarding airdrops from reputable developers in cryptocurrency.