Any coin where the creator knew that he was providing a suboptimal miner and kept a better miner to himself without disclosing this to the community
He is obviously talking about both Bytecoin and Monero.
Thankfully the Monero team (not to be confused with the original dev that launched Bitmonero) were on the ball and released optimised miners as soon as they were able to. This was all done while the total number of coins emitted was still pretty low, so the overall impact of that early period of scammyness was minimised.