I think Nintendo were in a bad situation with the wii u. It was a cheap ass console made from low performance components but there was one component that due to circumstances would soon be very expensive to get new orders of. So Nintendo couldn't manufacture more wii u's at a reasonable price so they rationed supply just enough to last until the Switch launch. That's why there were reports of older unsold wii u's being repacked to freshen them up.
The wii u started being manufactured by Foxconn in China but the last production was in Japan probably from unassembled parts from China.
http://www.kitguru.net/components/graphic-cards/anton-shilov/sony-may-leave-nintendo-wii-u-without-edram-cache/
I remember expecting the wii u price to drop but there was just no point because it was prohibitively expensive to produce more chips containing eDRAM memory so they just managed with their existing inventory of chips and stretched it out.
They probably could have re-designed the wii u to be compatible using different hardware but again that would be a huge expense for a console that wasn't popular. They were never motivated to make any further investments in wii u production.
It just feels like Nintendo have given up on the wii u for a long time simply because what's the point of marketing something that you cannot supply if you increase demand.
