Titan's River Deltas

The limiting factor doesn't seem to be the transport of sediment, it's rivers transported pretty efficiently. The sediment is more buoyant than on earth so for an equal flow it can carry a lot more sediment. It doesn't rain as often on Titan though so the overall time is a bit longer. Other factors could be affecting the lack of deltas including rising sea levels that are filling up the surrounding landscape. Tides and wind can reshape that sediment which changes what it looks like.