System Admins routines make mistakes with complicated host names and trying to acquire an accurate inventory is an absolute nightmare. This ties into IPv6 because why would anyone take that disfunctional system, which barely works with 'easy' IPv4 addresses, and make it even more complex? We would have to support both IPv4 and IPv6 simultaneously and firewall rules would get much more complex initially and they are already a huge issue for me to get changes made.
At my old job this was similar. Even though it was in the financial industry and that particular company was rolling in profits it couldn't keep enough network engineers around to save it's life. The turnover was high, documentation was horrible and projects to make things better languished on in the ether.
No no no, forget the whole IPv6 thing, just run IPv4 for all things internal and gratuitously support IPv6 outside if you really have to. I jest of course, but that is the reality of my corporate life in the last 6 years in two fortune 500 companies.