User names should not begin with a hyphen¹, so it shouldn't interfere with home directory references.
The child process point is an interesting one, I feel like you could workaround it by using a chpwd hook to export $dirstack and set it at startup(or a precmd function and $DIRSTACK if using bash). Something like `export DIRSTACK=${(pj#:#)dirstack}` in the hook and `dirstack=(${(ps#:#)DIRSTACK})` in the startup file. I'll concede this point though, as while a fun thought experiment the end result would be ghastly ;)
¹ https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1...