There’s a big difference between bycatch you can’t keep and being required to throw away all bycatch, I’m presuming that’s what you mean.
NOAA states:
>Fishermen sometimes catch and discard animals they do not want, cannot sell, or are not allowed to keep.
There’s a huge difference in not allowed to keep and we would keep for ourselves. If you’re netting a bunch of undersized fish you have to release them, I catch lots of undersized fish I’d love to eat but I’m not legally allowed to.
https://www.fisheries.noaa.gov/insight/understanding-bycatch