They can’t do 8 GB there are no 2GB HBM2 modules apparently and they can’t cut the amount of modules without cutting the CUs in half.
It’s essentially just to keep up some production volume this is their HPC die sold to the consumer market its the Titan V equivalent die of AMD minus the Tensor Cores just for much much cheaper.
It’s likely going to be a flop gaming wise, 2x8 pin power connectors put it at 300W TDP with performance only matching that of a 1089ti/2080 in the best case scenarios AMD currently has.
The 1080ti can be had for under $600 if you can find it the 2080 is around $700 but you get RTX and DLSS which while isn’t that useful yet is going to be more useful for gaming than 16GB of memory.