Well the term "theory" juxtaposed with "conspiracies" is also not that helpful because many extremely well supported scientific theories remain "just theories" because they are not of nature that they can be "proved" like 1+1=2. One crucial difference between scientific theories and conspiracy theories - the former can be used to make predictions that will be found to be true and useful - not in disagreement with facts, and novel. Conspiracy theories don't do that. They are just models developed by overzealous pattern matchers and they overfit the data. Therefore they have the feature that they are extremely poor about making accurate or useful predictions, and they are also very brittle. New data often has to be thrown away as fake and part of the conspiracy, or the "theory" has to be made even more elaborate and complex, adding new hidden variable type features that no one can disprove. How convenient.
For some reason UFO conspiracy theories, pizzagate conspiracy theories, round-earth conspiracy theories etc. etc. continue to fail to produce any actual new and useful results, no aliens have been demonstrated to exist, no Clintons in child-trafficking rings have been busted (even though DJT has all the power to do whatever Alex Jones asks him to make such busts happen), and no ice-wall or edge of the Earth has been proved to exist (should be damned easy right?). Oh, but of course, there is a conspiracy to hide all the evidence and keep everyone silent (when the government demonstrably has more leaks than a Welshman has leeks). Okay, that's the number one sign that a conspiracy theory is not a theory at all - because it cannot be used to make new and useful predictions because... conspiracies! Might as well call bullshit on all of reality at that point.
Therefore I say these aren't theories. I don't know what they are - hypotheses, conjectures, dogma, suppositions, speculation, riddles, tall tales, myths, or just plain bullshit. Perhaps we can recycle some terminology popular on the right and just call them alternative-theories? Un-theories? Or how about "spaghetti theories" as in Spaghetti Westerns (faked Westerns style movies made on a shoestring in Europe).