Ooff, yeah, though one.

If you start here where does it end.

I read this as:
Looking for a Half-Life Linux distro

Sure, that works too.

But based on OP it seemed to me that the larger intent is to get a Linux workstation set up in an AD environment. He wants to show to his boss it can be done, and this is the most integrated way.

Yes.

First you will need to get the VPN up (or be in the office, in the same network to be able to join the AD domain.

Then you need to join the AD domain using realmd. This will join the computer to the AD domain like any regular windows PC. It will set up the Kerberos client, DNS and everything for you (this part is done in sssd).

Once joined you should be able to access the network shares with SMB.

RedHat and deriviates have good support for this. So I would recommend Fedora Workstation, CentOS Stream or RHEL Desktop to set this up in.

docs: https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/7/html/windows_integration_guide/ch-configuring_authentication

I just moved to Ubuntu from Fedora Silverblue, for some $reasons. I regret it already.

Yes, I do this with Ansible :).

There are Flatpak modules and gsettings modules to set up Gnome to your liking.

I also build my own toolbox using ansible-container.

dotdrop, because different dotfiles per OS/hist is supported (I am usingfedora, Ubuntu, Debian, macOS but you can configure it as you wish).

NixOS is hard to explain.
I also did not get it at first, but got into a 101 session at cfgmgmtcamp last year and then it clicked.

I would suggest looking at YouTube videos like this one and try to understand what NixOS really is.

It is a pity really that it is not more approachable, the project would have more success if it is somehow easier to explain to others that are new to it :).

No issues running it in Flatpak so far for light gaming.