The are never enough core hardcore fans of any platform not even PS what Sony is good at however is consistently appealing to the mass market outside their core fans, it's this reason why Switch 2 is launching with at least a MK game as that's the biggest mass market game they have. The reason Switch sold is because of what I dub a four market approach it catered adequately to not only portable and home console consumers but also to red and blue ocean consumers while the platform also has the additional hook of a hybrid format.
The issue with looking at GC and WiiU is that the were clear issues in comparison to the more successful platforms but the main one is those platforms were chasing approaches of other platform holders that Nintendo had little understanding of in regards to what droved their success (GC essentially was PS2 lite while WiiU was a pivot from Wii towards PS3/360) where as in stark contrast Wii and Switch weren't trying to be like any other platform they were just being what Nintendo wanted so they understood how to structure themselves and handle the platform, case point is the 3DS it had a rough start but still went on to do 75m as they understood how to approach any crisis management with it.
Switch 2 is effectively following in the footsteps of SNES and 3DS in being one of Nintendo's more direct follow ups to a prior platform historically these have not matched the predecessor's success despite still being successful and tbh with the way the Switch is going I don't think that trend will be broken as Switch is possibly going to be the highest selling platform of all time which quite frankly is a monumental task to repeat back to back, I can see another 100m+ being repeated as a monopoly on one of the four markets helps especially if they go for another 8 to 9 year run but it'll take something otherworldly to better Switch's performance.
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