Any infrastructure that is of a size needing this will already have in-house tooling (Google/FB/Amazon/etc) and everybody else should be using public clouds anyway. Ubuntu is grasping for relevance.
But you do raise an interesting point, which is that all the MDCs have their own homegrown infrastructure (which incidentally they will tell you they love to hate, or vice versa). That is definitely true, and they are not MAAS target customers. But it's also true that they are not the only places where you will encounter large deployments of servers, and if you believe that at least a segment of the server market will go towards more/many nodes (a.k.a hyperscale), then having something to reliably deploy and manage a bare-metal cluster is definitely essential.