There are not airdrops nowadays. No one sends free crypto in 2022. Instead we receive scam BSC garbage tokens every time we make a transaction in our wallet. Airdrops are gone. Instead of airdrops we have referral competitions and testnet programs. Test a platform, wallet, network - get a reward. That is a current airdrop reality. Even telegram airdrop bots are more dead than alive, as I barely receive spam with a favor to join. I no longer even get tagged in twitter in crap airdrop programs either.
Well, the last time I took part in the airdrop was a few months ago, and until now I haven't gotten the reward that I should have received. it seems that it is currently very difficult to get rewards from airdrops, even though I participated in airdrops from quite large projects.
however, the potential is very small for now, even less than 10:1. the point is that out of 10 airdrops, 1 pays. maybe out of 15 airdrops, it's good enough if there is 1 airdrop that is really worth it.
as for the garbage token issue, I didn't even follow any airdrop to get it LOL.
I can add to your exchange rate of 10:1 or 15:1 the fact that received airdrop token value might be much lower than transaction cost. Either you get an Ethereum token and its trade will never cover transaction cost. Or you get a BSC token, that is traded on a DEX, where you first enable transaction, then swap. I think airdrop participant will end with 0 profit in this situation.
Personally, I have stopped participating in airdrops when "Ethereum transactions became expensive". And all projects that are on BSC blockchain and ran airdrops, turned to be scam. If in 2021 airdrops were unprofitable, waste of time, then in 2022 it is better to skip them at all.