Because of Genesis 6:1-4, rebellious “sons of God”. IOW, rebellious angels that Peter & Jude mention. And their offspring the Nephillim.
More later; it’s late.
But I found this:
The Oronteus Finaeus map (Oronteus Fineus map) shows an ice free Antarctica. As well as the Piri Reis map their exists another anomaly. The Oronteus Finaeus
www.climate-policy-watcher.org
How would such information be available to ancient - therefore primitive (as would be claimed by modern secular authorities) - human civilization if it weren’t for these rebellious powerful creatures who materialized as humans to take women, “all whom they chose”?
According to the Gospels, these ‘demons’ can possess animals. Remember the “herd of swine” that went over the cliff?
At Genesis 6:1-4, Pre-Flood, they apparently materialized as men & began sleeping with women!
No wonder God stepped in!
The Tartarus they were thrown into, that the Apostle Peter mentions… this debased condition - apparently prohibits them from materializing today, but they still manifest as “apparitions” & pretend to be “dead loved ones” to mislead.
IMO.
Because, to me, the dead are dead. They “know nothing.” Ecclesiastes 9:5; Psalm 146:3,4.