Well if these bundled applications are what you get when you buy
RHEL
than I would say the distribution is in some sense closed. Whether they
are required for the system to run seems irrelevant. They are part of
RHEL. Or am I not understanding what you are saying?
They are bundled with it, not as part of it. People like the FSF consider
it important that such things are kept separate so that people who choose
freedom can separate the free and non-free easily.
Whether it makes it "closed" is a matter of personal definition I guess.