One point I'd make here:
They may be free to "speculate", but they aren't as free to say "publish" something on a topic like EU theory for instance. When they do speculate, there can also be a professional and financial cost for that speculation. The herd mentality can have an effect on both types of groups and the financial and professional fallout can be much more severe in "science".
All someone has to do is write up a proper paper if they have a notion that seems to run contrary to the currently accepted position on a particular scientific issue. Like, let's say maybe a fellow believes the Sun has a solid iron surface, for example. All he has to do is prepare a legitimate presentation and submit it through the accepted channels for peer review. If there's anything to it (of course that iron surfaced Sun thing is a totally made up example of a ridiculous idea) then it moves through the process of scientific review. When it comes out the other end,
if it's right, it's ready to be blended into the consensus position. But if it's wrong, it's wrong, paranoid conspiracy theories notwithstanding.
Of course it helps if you start by proposing something sane and rational, and you
must be able to support it with evidence, not just talk. In astrophysics that means assembling a lot of data, understanding physics, and having the skills, or at least the resources, to rigorously explain the proposition using math, which is the language of physics. If you have no evidence, if you don't understand physics, if you can't do math, then you're just crap out of luck, aren't you?
Many crackpots whine about the persecution conspiracy, that "financial cost for that speculation", but of course no evidence for that exists in modern times. If someone is proposing a change in the way we look at some area of science, if what they offer is really valid and supportable, if they have the skills to assemble it into an objective, understandable presentation,
and if they have the balls to present it through the proper channels instead of just bitching and moaning on Internet forums, the world of science would welcome the opportunity to apply the new material.
Rejection of a crackpot idea has nothing to do with being stifled by possible "financial and professional fallout". That's just a silly paranoid excuse the crackpots use for failing, when it really comes down to the fact that they really don't have the science, much less the skills or the balls to make their case.