Yeah you got a point, I'm sure the new GR86 and BRZ will also be very tuner friendly as well.
I think it might just be a European thing, i did some more reading on the Supra thread and they talked about using Bosch's new ECU which apparently affects BMWs and Audis and probably other European...
The only known issues that the VR30 has right now is the belt, and then there was an issue with oil (they said to add half a quart more)
Another small issue is the direct injection, can be fixed with a catch can to help with the carbon build up.