I don't quite agree, Active Directory is an easy to learn and deploy implementation of LDAP, Kerberos, and DNS (often in combination with CIFS) with a friendly GUI interface. It also adds Group Policy, which is less simple to replicate on Linux. Then it adds a huge pool of admins which have been through the vendor supplied training process. I can show people how to create a user and add them to my company defaults in minutes, and not just because they are familiar with Windows, but because they are familiar with the desktop metaphor
I am a keen Linux user, I am typing this on Linux in fact. We have lots of processes running on Linux in fact. But I cannot replace the ease of AD in Linux. And more than that, our ERP client only runs on Windows...
If you're using Red Hat/Fedora GNOME desktops, you can pair that with Fleet Commander to set up desktop policy: https://fleet-commander.org/
At some point soon, I expect it to work for SUSE and Mageia systems, too.
I currently run this on a Fedora Server setup to pair with some Fedora Workstations I manage.
This is a big plus for locking down mostly untrusted users (eg average employees in a larger enterprise).
Edited to fix stupid autocorrect.