"...like how the Wii U was abandoned even though it was "technically" still being sold"
What? VGChartz still did track the Wii U after Nintendo stopped the production FOR MONTHS. The point where they stopped tracking it was when the Switch launched.
"Physical carts are being halted outside of Japan early next year..."
That's something that I don't understand. Sony is still selling PS Vita retail Software in the west but VGChartz has stopped tracking them. I would really appreciate it if the people who are behind the sales could explain this to me.
I stopped tracking it because the numbers we were getting were too low to produce even half decent estimates outside of Japan. I still get data for Vita, DS, and even PSP software in the west, I just don't publish it for that reason.