CapnZapp
Legend
If you are talking about the warlord, that argument will only infuriate its defenders.But, at the end of the day, the leader has been covered. There's a feat, a bard subclasses, and two fighter subclasses that touch on its abilities. Each of those appeals to some fans of the archetype. There's less pressure for a full class, which would also make those options redundant. In contrast, there's a lot of other builds and archetypes that haven't been covered once, let alone four times. "Not perfectly replicating a class from an old edition" isn't a strong enough reason to go back to it again.
Efforts like the purple knight does nothing for the Warlord fan, and so it is a poor argument for not providing a real Warlord.
There is no existing or UA subclass that comes even close to what the Warlord fans want: which is completely magic-free healing combined with a sturdy chassis for "remote controlling" your allies.
Somewhat like the battlemaster maneuver subsystem but with all the choices geared towards using your allies as playing pieces.