I think you might have failed to realize what will determine which cult people will choose. When the Media cult makes their presentation, they'll be reduced to showing a movie (or equivalent, maybe a lo-fi virtual reality) and saying "look at this fancy media we can create, wouldn't you like to be able to do that?" But then the Physics and Mathematics cult (I really do fail to see how they could be separated successfully) presents a light bulb, a tesla coil, and possibly a miniature sun and gets to say "this isn't even the half of what we could do if we wanted to. If you want to know how to do it, you'll have to deal with us."