Using any enchanted or nonenchanted fishing rod no longer produces any fish or "garbage" items; enchanted fishing rods, enchanted bows, enchanted books, nautilus shells, nametags, lily pads, pufferfish, & saddles are the only obtainable items.

I've done a 100-run test using a fishing rod with Unbreaking III & Lure III (no Luck of the Sea) & here are the results: 21% of the loot was books, 18% fishing rods, 15% bows, 14% nautilus shells, 14% lily pads, 9% saddles, & 9% nametags. I recalled that the pufferfish I have was obtained by directly killing them in a warm ocean.

I've also tested with unenchanted fishing rods, but doing a 100-run trial would take a long time. Suffice it to say fish are still unattainable that way.

This was tested in a beach biome & cold ocean, I believe.

The screenshots display the following, in order: fishing rod enchantments, 25 runs, 50 runs, 70 runs, & 100 runs (chest filled up before I could get to 75), & the items organized by type in the last two screenshots. If fore whatever reason the screenshots aren't in that order, refer to the file name, i.e. Screenshot (6-14).png.