That's why. Laypeople lack almost all the tools necessarily to evaluate research and slick presentation, even when couched with "I'm not an expert - make up your own mind" can be quite effective and completely misleading people.
I think there is a big problem with people not not having any understanding of how much work it actually takes to become an expert. The narrative of "outsider dabbles in some field and makes a big breakthrough" feels reasonable. How hard could it really be to break into one of these fields? This sets them up to be misled.
Yeah, I think this is the right way to do it. "I'm just explaining my weird theory" is not a good approach to fields that you know little about.
No system is perfect, but I'm way more likely to hold correct opinions using this approach than most other approaches.
Whether Hancock is a celebrity is neither here nor there. Proper science is supposed to be above personal attacks.
There are funerary temples lousy with inscriptions outside, but anybody can build those anytime. Crypts elsewhere are scribbled throughout.
We still know very little about the pyramids, so cannot contradict speculation. The official story / timeline is just one such.
Anybody can co-opt a spare pyramid and scribble it up. There is even an absurdly sparely applied term: usurpation. Usurping one of the Giza constructions would raise eyebrows, but the others could tempt, if in good shape.
Once one's immediate predecessor is securely dead, actually expending on a fancy interment is not strictly necessary, given nobody can see inside anyway. Lots of crypts were left comically incomplete, later. Even Menkaure's pyramid was not clad as specified.
Later they must have got the idea of having supporters demand to tour the crypt before it was sealed, to make sure things were actually done. You probably can determine which successions were ... unfriendly by how incomplete the funeral chores are.
For me, that point was somewhere in the first episode. Sorry, after watching Van Daniken (sp?) and the Ancient Aliens crew use misinformation and "asking the question" type fallacies to basically ruin widespread understanding of history all I can say is "fuck that guy in particular".