Airdrops aren't always waste of time, it depends on how good you are with them, the easiest way if detecting a good Airdrops is to watch the rating on top Airdrops platforms like airdropalert or airdropbob, if it's rated 5 starts it's probably because it's listed on coinmarketcap and it's trading
Airdropalert and other such websites are just bullshit. I used to join the airdrops with 4+ ratings in late 2018, almost none of them are worth above 5$ except one, I guess its WAN or something like that. If the tokens aren't worth atleast 5$ what's the point in doing those airdrops. Tbh, most of them are worth 0-1$, a few of them around 2-3$.
I would say that even doing altcoin bounties are not worth your time unless you are unemployed or from a third world country where the financial situation is poor. I would suggest you improve your posting quality and try to get a spot in the Bitcoin paying Signature Campaigns.