There are some interesting parallels of giants in ancient cultures, traditions and histories of nearly every culture on earth.
Basically the same story. Gods came to earth from the stars. They mated with daughters of man. Their children were giants. The giants were killed long ago. Sound familiar?
There are some interesting conspiracies, A compelling one is that from the 19th to early 20th century, US universities were funded and even published archaeological studies in journals and newspapers on giants found from digs. The skeletons were deposited in the Smithsonian Institute. Modern attempts to examine these "Nephilim" have resulted in the Smithsonian saying no such skeletons exist.
While claims have been debunked
https://www.reuters.com/article/idUSL1N2ZG1I0/
I seems strange why prominent academics in this era were funded to look into giants in the first place?