I have to make one correction: The original author of the theory seeing the pyramids as huge chemical reaction facilities is Geoffrey Drumm who published his book about this in 2020 and started his research on location in Egypt in 2017. On his youtube channel he has a video about the Red Pyramid published in 2021.

Geoffrey Drumm
[thelandofchem.com]
[youtube.com]

This theory about the chemical reactors I see as reasonable and well researched in many details. The perfect match with the old name of Egypt, Khemet, tops it, with the connection to today's Chemistry.

Also interesting the details he provides about Fritz Haber most likely having visited the Red Pyramid shortly before he invented the famous Ammonia industrial level production process.
and potentially paying hommage to the Red Pyramid's chambers with presenting the third reaction chamber of his process elevated above the 2 others, which is not needed for pure physical and chemistry reasons.