It's worth noting that the Xenu story is only told to people who reach OT III. Because the cost to reach that point is
around $159,250, (and is invite-only, anyway) about
10% of Scientologists (possibly fewer) even reach that level.
So, perhaps for those lower 90+% of Scientologists, it is just a pseudo-mental therapy cult. As for those beliefs being allegorical or not, Hana Eltingham explains in the documentary
Going Clear that, even though she knew that there were holes in the story (like the volcanoes that LRH name-dropped in the story weren't 65 million years old), she took the story literally enough that she fell into a deep depression, since this meant that she'd never be free of the Thetans) and she almost jumped off the roof of Big Blue. She only decided against it because of the negative publicity it'd give the Church.
But as for the distinction between a cult and a religion, honestly, I'd say the distinction is largely academic, but that would imply that there was some degree of agreement as to the criteria that distinguish a cult from a main religion. I might guess that the biggest distinction between the two is that a religion has some degree of mainstream credibility and a cult doesn't.
An Anti-Stefan Molyneux site I read, while trying to assess whether FreeDomainRadio counts as a cult, decided to create this flowchart to try and distinguish whether or not it counts in his attempt at even trying to figure out what a cult even is:
Of course, as the author he points out that "The Chicago Bears, the marines, people who have every book Stephen King has ever written, Methodists, and devoted Jonas Brothers fans" fit under this definition of "cult," so he zeroes in on destructive cults, which he identifies as your Jonestowns, your Heaven's Gates, your Aum Shinrikyos. By this flowchart, it would appear that Scientology qualifies as a "destructive cult" and most mainstream religions qualify as "cults, but probably not destructive" (at least not in the same way those groups are).
This article might be illuminating in that it explains a scientist who decided to give MBTI tests to converts to cults (present, as they would have answered in the past, and would expect to answer in the future) and found they seemed to have changed MBTI types and converged to a few specific types (with a specific convergence towards a specific type.) This may be part of a phoenomenon that Aum Shinrikyo leader Shoko Ashahara called "cloning the guru."
Meanwhile, converts to mainstream religions tended to stay the same, personality wise. Scientology was one of those groups where personality types converged. Which type the Scientologists converged to isn't explained,
but it is said that "In three of the groups the movement was toward ESFJ. Two moved toward ESTJ. One moved toward ENFJ." Despite the book's saying all relevant information is included in tables in the appendix, the tables all refer to the main Boston Church of Christ study. I suspect that, with all that fucking coursework, they might be one of the two ESTJ groups.