People trying to market things create a lot of new terms. They don't want to seem like they're selling the same old thing, but something new and innovative.

Occasionally, the new term is warranted, of course, but that's far less common than simply trying to appear different.

It pretty much is the same, the only change is the level of abstraction. Apparently the easiest thing for everyone is just giving the user access to the whole damn OS via a container, rather than have them deal with vendor specific mainframe minutea.