For a lot people I think who bought the wii u, the realisation was it was very poor and there was a lot of negativity about the console but the Switch launches with an amazing game and at least for sometime it will be seen in a very positive light.
It's possible the only difference is the cliff edge where sales drop dramatically is just delayed with the Switch. It seems to me though with April Mario Kart that cliff edge is more likely around May/June. There is also the online charging to come and a greater understanding by a wider audience the very low performance level of the Switch. The wii u had a lot of multiformat games reviewed that basically criticised the wii u as the weakest which probably did a lot of damage to wii u sales. Such Switch reviews haven't really started yet. I think generally people don't want to buy the weakest versions of games even if it gives them portability. The realisation of the wii u's very low performance level seemed to have been a similar time to the huge drop in sales.
It does seem to be for me at least the wii situation. I was amazed when it sold well being basically just a gamecube with a motion sensing controller and games having a very limited performance level but the wii sold far higher than you'd think based on the sum of its parts and the same seems to be true of Switch. It maybe took me 2 years to get a wii possibly more and I only bought a cheap japanese model that was £45. I thought it was pretty awful and was mainly playing my gamecube games on it. At the time most of the games were dire and a throw back to the last generation in performance. I know its often claimed the failure of wii u is based on consumer confusion about whether it was a separate home console or an accessory for wii but I think low satisfaction levels with the wii was also a factor. At the time the wii was criticised as a dust collector.
