Airdrops are tasks that cannot be certain to get the best out of them now. They are tasks you just participate in and then wait to see what will come of them without hoping for anything in return. This is not even about the gas fees you’ll need to be eligible for some of them, the truth is that airdrops are not paying like they use to in the past, there are bunch of them that are going to just be worthless and waste of time. Since you don’t know the ones that will pay, if you know you can spare your time and energy into doing them, then there’s no harm in trying them out, they’ll just be worth it in the end or not and you have to just live with the reality of it.