So coming back to this it's starting to become a serious problem. NxFileViewer is good for extracting the base NSP, but it can't handle updates in any meaningful way. Yuzu too seems to extract only the base ROM, not updates. The only way I could figure out to extract stuff with the update before involved using NSCBuilder to repack without a key, but NSCBuilder seems to be abandoned right now and no longer works (in particular it can't update nutdb anymore, so can't get the game keys.) I never successfully managed to extract the game keys the hard way before, so the old hactool method is basically a no-go for newer games now. At this point the only thing that seems to even work at all anymore is indeed installing to the Switch and then extracting on the Switch which is an incredibly tedious (you have to hook up the switch and install or transfer through network which is also slow and install from the card which also takes a while then fire up the dumper and find the game then dump romfs with the update which it does not default to doing,) slow (I have a fairly fast memory card, but it takes at least eight times longer than on my PC,) and resource consuming (it needs twice the space to do it which is a problem on a limited memory card) process. It's just a real mess. There has to be a better way?