The difference?
Pokemon, which Nintendo owns.
If I was an investor, I'd view the potential for licensing the Nintendo IP (something Nintendo has been extremely reluctant to do in the past) as a huge potential growth vector for a struggling market segment (consoles, specifically Nintendo-made ones.)
It's not successful because it's particularly innovative or a fancy piece of tech, it's a success because it's pokemon.
You wouldn't go around comparing the popularity of Doom to Facebook right? This comparison needs to disappear.
Just because something doesn't get widespread news doesn't mean it's unpopular. Sure, Go is massively popular in its own right and to scale beats out Ingress but it's not like Ingress was some 2-bit game that nobody played. Half the mechanics of Go came from there, if Ingress sucked and was a failure they a) wouldn't have put the same features in Go, and b) probably wouldn't have even made Go.
tl;dr Please stop shitting on something you have zero experience with.
I don't use it at all anymore.
Either way, I expect Nintendo will finall be releasing more mobile games. I suspect investors think the same thing, leading to the $7b increase.
Sony will live or die based on their ability to make great tech. Nintendo is different.