Before we had monofilament, one of the many wonders of the world of plastics development, fishing line was braided thread, cotton for the most part. Like Henry Ford's Model T, it came in any color you wanted as long as it was black.
That's an exaggeration. There were other colors, like green. But black seemed the predominant color of that old line. Remember, much Arkansas fishing was in muddy oxbow lakes and backwaters before the era of multiple man-made lakes came forth.
Visibility in that water was a matter of inches, not feet, and not many inches at that. Fish evidently fed by smell, not by sight.
But fishermen caught fish on the black braided line of the past. It worked fine because there was no other choice. Yes, old line became brittle and easy to break. More than one debate took place over whether braided line was stronger or weaker when it was wet, like after several casts into the water.
Some anglers today insist that braided line held up better in sun than today's monofilament does. Sunlight can make the plastic line deteriorate, experts say.
Bottom line on line: Change it. Change it even if you think it doesn't need changing. Fresh line performs better and also gives you the mental asset of knowing you are fishing with the best of equipment in regards to what connects the rod with the bait.