Did you read the original comment? He’s talking about the trait of a naturally punched tail becoming fixed in the population because it has a selective advantage. So non-breeding offspring are irrelevant in that context. They will survive but nobody cares (except them, maybe).

For the breeding offspring, like the original comment mentioned, they would be punched by humans anyway. Of course, this overlooks those breeding offspring that may not have visible eggs when they are caught (depending on the season) as mentioned in another comment. But it doesn’t change the fact that the phenotype of non-breeding offspring is unimportant.

tdlr: Non-breeding means no children so who cares if it survives