i changed one on a 1998 Toyota in 2012 after 90k miles, and there was nothing to see. Peeking into the tank it is just stainless steel. In the sock was just 2 grains of sand.
The filter just looked like wet cardboard paper. Then it dried out it looked like the color of regular cardboard paper.
The rumors that the bottom of your tank is full of goo and sediment are untrue unless that is what you are putting into your tank to begin with.