It's indeed a bit old menu, and I guess most people fish with direct [a]pplying of the item. But it's no biggie to add filtering to "Tools" only if "Set a net" option is chosen so let's do it. Inventory list doesn't really have functionality to show only specific item types, eg. nets, so the restriction/availability is item category based.
For me adding fishing gear crafting and hook apply options to Fishing menu doesn't feel that necessary, but it's quite easily doable as well.
Maybe something to consider in the future.