I will make 1 editorial suggestion to your first sentence. A reason for hoaxing is it is supposed to give the hoaxer a psychological feeling of gratification, thinking they are outsmarting people. Sadly, many politicians, criminals, and other shady characters use a similar principle to justify their actions.
For BF hoaxing in particular, it's a lot of work to be convincing. Even with powerful video and imaging tools these days, a person would have to be really into their own psychological bubble to spend time doing that. It's like a job to plan all of it out and try to pull it all together. This is how law enforcement approaches profiling for serious cases. There are only so many unhinged people spinning like that. They don't just leave the clues of the crime or hoax. They have left traces of their practice runs somewhere else to be found. In fact, the hoaxer always leaves that easter egg, intentionally or not, that leads to their undoing. They want to see how far their act can go. What funs is causing mayhem if there is no chance they will get caught?