Is it possible to set different themes for light and dark mode? Otherwise it won't really help with identifying if you booted into syscfw instead of emucfw, since they share the same atmosphere folder.
HOS apps running on emunand/emummc not being able to access sysnand/sysmmc is true though, since the redirect is done on CFW level.
That HOS apps running in sysnand can in theory access the emunand, if they have access to the dumped keys and since they can in theory open the raw sd, is a different thing, not not really relevant for any app accessing the nand/mmc as nand/mmc via fs, since that will always depend on what you bootet into, and won't be detectable by any app, unless they communicate specifically with exosphere, which I don't even know, exosphere will allow.
Also as mentioned, talking about rcm payloads is not relevant when talking about apps in HOS and will just confuse everyone that doesn't know a lot about the topic and stumbles upon this topic.
People would have to read into the conversation in order to be "confused", but information has been progressive to satiate those as far as they want to go. I don't get the gatekeeping, as it was a personal interest of mine to understand the recent developments of the scene. I don't use DBI and am curious about the appeal. If it is still under development, then I don't understand why it would be largely ignorant of the fact that emuMMC is a thing, or specifically, THE thing.