I was speaking to a friend lately. He wanted my opinion on buying the $70k+ NA2 Coupe that's for sale now. I mentioned that for near $70k you can buy a much better car than an old NSX, namely the Porsche GT4. There's no way i'd buy an NSX now. That ship has sailed.
I don't disagree with your assessment, once you start getting in the $50-60k range there is a lot of competition. However, you are taking in to account only the initial sale price of the car. Sure both cars cost $70k, but with the Porsche you have depreciation & maintenance that are going to add up to a significantly higher overall ownership cost than a $70k NSX. Since we are talking assets, it is important to be factoring in the buy/sell price and that is where the used NSX will financially make for a better purchase than the Porsche. Of course, the Porsche can drive circles around the NSX but that is a different matter
I do 100% agree though that the bargain ship has sailed. NSXs are no longer a hidden gem/outrageous deal that they have been for years. They are still a good, solid buy though as long as you do your homework.