I strongly disagree here, airdrops do not build communities anymore. There are too many people who consider farming airdrops as a job, but that is very bad. You can look at any project that has a good airdrop to confirm my statement. As soon as the airdrop farming is over and distribution has been done, the activity in their telegram and discord drops dramatically. This means that in most cases airdrops are not effective at building a community, instead they only attract farmers who are stealing money and moving away.
In the first place, the airdrops that require you to spam Twitter/Telegram/Discord are bad by default anyway. Not a single decent project founder would ask their community to spam for token share.
True. Most projects that require you to spam and create hype don't end up paying or the token is worthless and some even untradeable. I think it's better to find good projects first and then search for their airdrop options if they have one. That way you at least earn decent tokens which would usually have some value later on. It's better to have a few airdrop coins that have some substance rather than having 50 tokens that are worthless and only good for occupying the space in wallet.
Now I have noticed there are countless airdrops on telegram and again the same story, 90% of them are scam. Most of them require you to click to earn the tokens and I never understand how these projects make any sense. Last such airdrop/giveaway I was part of, was Hamster combat and it was fun but the tokens I got for the time invested in that was not worth it.