Honestly with the past results of some testnets, users were discourage to do some of these task due to low rewards. Example of these are sei which has a very low value due to massive participants and a very few alloted budget for the testnet. Also the sui which chosen to do a random whitelisting which ignored the testnet users full activity and opted to do a small group of people reward by random lottery. Well some also low class projects giving a false hope and only non valued nfts.