Your choice of words there is harsh and uncharitable. I don't know why you did that by calling those who do it "foolish". I wouldn't call anyone who's making a legitimate hustle and earning from it foolish, even if I don't like what they're doing. I've profited from some of these tap2earn you classed as foolish and will still earn from more to come. Your advice should've been that those who indulge them should do their own research (DYOR) and be careful, not that they're foolish.
Agreed, not all tap to earn is going to turn out to be a scam but newbie should know that alot of them are going to waste their time. Most of the project don't have a plan after the Airdrops, they're just launching without a team or plans to develop the project further. You can notice this when they start asking for money to receive the airdrop, it's the money that they intend to use for exchange listing or they scam and run away with the money. Most of the tap to earn projects don't have a team but just started by one person in his basement.
For those hunting for this tap to earn Airdrops, they shouldn't put all their hopes on anyone to be successful because the most popular ones that everyone is talking about can still be the most scam as after they get the money, they can decide not to launch and since people don't know who the faces behind the project are, they'll be free.