Another article about the same case makes this smell even more like The Onion: https://www.mtvuutiset.fi/artikkeli/vanhempansa-pakastanut-mies-perustelee-tekojaan-jopa-muinaiset-faaraot/9391918
An elderly doctor says he froze his parents’ bodies at his father’s request. During police questioning, he spoke of pharaohs, catacombs, and Elon Musk.
“My father’s wish for me, as his eldest son, was that his body be mummified and preserved, and not disposed of by society through cremation or burial,” the man said during police questioning.
He says his father advocated for “ecological diversity, a pleasant lifestyle, and freedom of religion and funeral rites.”
“Even the ancient Egyptian pharaohs spent half their lives preparing for death. So did the richest man in the world, Elon Musk, who wants to be buried on Mars. I’ve heard this from my father before.”
According to the son, he was supposed to build a burial chamber for his parents. At first, his father had asked him to build the burial chamber in the United States. The family’s third child, the sons’ sister, has lived in the United States for several decades, and according to the son, his parents visited her there every summer.
“My father believed that his body would remain ‘forever’ and allow future archaeologists—if they were so inclined—to study what the human body was like back then. This isn’t some delusion of grandeur, but rather a product of the thinking of that era,” the man explained.
He said he must fulfill his father’s request to the end.
“This must be seen through to the end. I have promised, and I have a sacred duty to build the burial chamber and prepare the eternal coffins,” he said.



There are also swamp mummies that happened because the swamp may lack oxygen that is needed for proper decomposition. Those are not human-made, of course
Some are human made, sure it’s just by dumping a corpse into a bog, but we have evidence of the Irish doing just that (though we don’t know if it was to preserve them)
Oh, TIL, thought it’s too random for use by humans