Regarding retrodrops and airdrops I still see some issues:
1. Most of them are not announced in advance and users should proceed with activities only based on rumors and you can't be 100% sure that something wouldn't go wrong. Many airdrop hunters expected a retrodrop from SUI and it ended being a waste of effort once it went public.
2.You need to pay the transaction fee with your own money at the time of activities. And if it is some kind of ETH L2, then these fees can be high, although you cannot be sure that you will not fail on some criteria or the retrodrop will take place at all.