Coins not exempt are
-Clones not older than 8 months. If you cloned another coin and just changed the rewards, your on the list.
-IPO coins.
-Premine greater than 1%.
-Devs that have no idea on what their coin is or how it works.
-Fake coins or coins that clearly have no intention of development.
It is an error to use percentage. 1% of 1M is 10,000 coins at 1 sat = .0001BTC - not worth the effort scamming. 1% of 1B is 10M coins at 1 sat = .1BTC - worth scamming.
Of course many coins either have lower coins with higher % of premine or 10, 20, 30 billions of coins with 1% of premine but if they get to sell at 10 sat - 1 BTC or more.
In essence there should be no premine or any premine to be done in terms of number of coins needed for so-called development. The number of premine coins can be converted to % to get a general idea. If anyone is serious about premine then there could be a team of anti-scammers, i.e Operation Shitcoin Cleanout and Clean Up could hold a cold wallet and developers of any new coins would be required to send the premine coins to be kept in storage. When they have fulfilled their conditions of development, premine coins could be released bit by bit by sending 'payment' to the developers from the cold wallet in storage. This, i believe, would then reassure the miners and investors that the developers get nothing until they have done their part and makes the coin resistance to dumping.