This Ram information is as good as we could have possibly expected. It's not simply going from 4 gigs to 12 gigs, the jump from LPDDR4 to LPDDR5X is huge in and of itself. It really shows that the Switch 2 is a true generational leap over the current Switch, and is much better than the RAM specs Digitial Foundry used for its testing of 'approximate hardware' a while back.
With the og Switch, how much would it have even benefited from having 8 gigs of RAM as opposed to 4? 8 seems like a waste given the bottlenecks of the RAM speed and the limitations of the chipset.