The only proven way to downgrade a PS4 involves complex hardware modification. This process is known as the "Syscon Revert."
Because 1.30 is so close to the exploitable 1.76, many users assume that if they could just "downgrade" their modern PS5 (running firmware 11.00 or higher) back to 1.30, they would have total control. This desire birthed the search for the file. ps4 downgrade 1302 upd
Common downgrade strategies (high-level, non-actionable) The only proven way to downgrade a PS4