I have not read the article but
there is catch and release then there is
catch and catch and catch and catch and catch and catch and release and release and release and release
here is what they may be talking about
Option 1, catch and release an limit = fish has a chance.
Option 1a, catch and release many limits of fish and according to many studies more will die then if you just killed your limit
Option 2, catch and eat = fish has no chance, but the other fish in the lake do live
Option 2a, catch and eat then keep releasing many limits = fish has no chance that you ate plus some of the released fish will die
Option 3, dont`t fish.