Seems about right to me. Games are getting large so 512 gb storage is right. 12 gb ram is pretty normal these days. My cheap laptop has 16 gb. Memory speed is arguably more important than amount.
Switch 2 is going to a very nice upgrade over the current Switch. I can't wait to see games like LM4 and pikmin 4.
I'm standing by my prediction of xbox one and ps4 arena of power. When new hardware is on the way it is always overhyped. The ps2 and the famous FF8 dance scene. The ps5 and 4k 60 fps promises. The list goes on and on. Switch 2 will land slightly less powerful than the rumors are suggesting.
The most important rumored spec is the 8 inch LCD screen. This means the console itself will be a bit bigger than Switch, allowing for a bigger battery to be implemented. This doesn't mean that Switch 2 will have longer battery life than the original Switch though, but rather that Nintendo aims for not falling below the 2.5 to 6 hours range of the original Switch.
The rumored specs for Switch 2 are a bit beefier in comparison to what Switch was for its time, so there's really no way around making the console a bit bigger to accomodate for the bare minimum of acceptable battery life.
512 GB internal storage are also eight times as much as good old Soundwave suggested for a cheaper $399 SKU. The series of rumors also suggests an updated game card format - as has been par for the course each generation since the introduction of game cards with the DS - so a more modern solution for external storage should be a given too.
All in all, it looks like Nintendo is targeting a sensible spec sheet that makes it feasible to launch Switch 2 at $399. This is worlds apart from the catastrophic rumor mill that heralded the Wii U.