I cannot help with your actual but this is giving me mild ptsd flashbacks to everyone on hn/slashdot constantly repeating how simple and perfect unix security is, just use user accounts!
As if the most valuable thing on my pc was running a program on the gpu or the printer as opposed to my email account.
No need to go back to the Slashdot days. Look no further than 2 days ago to find someone arguing the kernel is uniquely important (here for reliability): https://news.ycombinator.com/item?id=49181366
On unix your email account is part of the filesystem.