When it comes to any issue like this I have a couple of levels of how I judge things (and yes, I do judge things).
The first is whether it is or isn't healthy, in my opinion. This has more to do with the specific situation and the people involved than judging any particular way of doing things. Usually, this has a lot to do with whether or not the people involved are happy and content and fully consenting.
Then I have what is right for me - something that I would entertain having in my life. I can talk about what is or isn't healthy for me in a relationship. This is, by definition, a lot narrower than the first one.
I have a problem with the folks who bash the hierarchical style of poly. If they want to say "it may be fine for others, but not for me", then that's fine, but to say that it is automatically an unhealthy way of having a relationship is, frankly, insulting to those that make it work, in the same way that saying monogamy is somehow inferior to poly (or saying it is "unnatural") is insulting to those that are doing a great job of making it work. Are there some who are doing hierarchical poly really badly? Yes, of course! There are folks doing each style of poly and each style of monogamy really, really badly. But I'm not going to be throwing the baby out with the bathwater - it doesn't make it RONG (to coin a spelling style I have seen elsewhere).
I think that linking the idea of hierarchical poly to the word "cult" in the title is inflammatory - the written text of the OP makes it plain that she is talking about *some* folks who turn it into a cult (presumably implying that it is unhealthy). A "cult" can be seen as any group whose beliefs or practices are considered to be abnormal or bizarre (that's from Wikipedia) - by that definition, from the perspective of the mono world, the whole of poly is a cult.
To go further, an aspect of cults is that "some form of coercive persuasion or mind control is used to recruit and maintain members by suppressing their ability to reason, think critically, and make choices in their own best interest" - I think that we have all seen poly situations whether this applies, and I would tend to agree that this often manifests itself in hierarchical relationships, often with a big dose of d/s dynamic thrown in. Often these are done as an ego-crutch for the narcissistic dominant in the group. We've all seen it, I think, if we have spent any time around poly discussions.
So, in a similar discussion to that which happens with religious cults, the question is whether or not this is by definition bad for the participants. Are there such things as "good cults"?
I am in a mono/poly relationship (which some have said is unhealthy and can't work in the long run). It is by agreement of all involved hierachical in that certain compromises have been put in place to make sure that everyone gets what they need. I would not even begin to suggest to anyone that the set-up of my relationship structure is some model that everyone should live by - I know it wouldn't work for a lot of the folks on the poly boards (most of whom I have a healthy dose of respect for), but does that make what we are doing bad, or a cult? There are quite a few relationship configurations that others espouse, or live by, that I wouldn't even begin to consider in my own life, but that doesn't make them automatically unhealthy, as far as I am concerned.
"Listen, or your tongue will make you deaf." - Native American Proverb