Technically, Islam is pretty much OT from the Ishmaeli-descendants’ perspective. Islam also adds a bit of Jesus to keep up with the times (for 7th century). Heck, if Islam originated in the 19th century, it would have added bits of Sikhism and Bahaism. If it had originated in the 20th century, a bit of Scientology would be there as well. L. Ron Hubbard and ole Mo are pretty much the same.
“L. Ron Hubbard and ole Mo are pretty much the same.”
I think Joseph Smith is a much better comparison. They even use the exact same excuses as to why the previous holy books from religions they claim to be the rightful heirs to are not reliable. They also both claimed visitations from angels and direct revelation to a single person as the source of their Scriptures.