Personally, I would not describe the Land Cruiser inventory as a "ton", in fact I would say its very low when compared to other SUVs, particularly for the US market in the luxury offroad segment.
Comparing those metrics to availability of 2015 or newer G-wagens, GX460s, etc... or pretty much any SUV. Chances are, there are significantly more of them for sale then a few hundred for 7-8 MY.
Also, I find it hard to believe that your '13 LX was worth $70k this summer and a few months later it's worth $45k. Either your LX wasn't worth $70k then or its not worth $45k now. What is the mileage on it?