Based on this list, it looks like you have to be sitting on a 2022 or earlier non-updated PS5 to have a chance at the 4.51 or lower firmware to use this. A chance it’ll open up to other firmwares and as said maybe there’s a limited functionality 5.xx exploit on the horizon, but just a bit of reality before you get too excited.
https://www.reddit.com/r/PS5_Jailbreak/comments/1fhlyjt/guide_to_find_the_firmware_version_of_a_sealed/
Based on this list, it looks like you have to be sitting on a 2022 or earlier non-updated PS5 to have a chance at the 4.51 or lower firmware to use this. A chance it’ll open up to other firmwares and as said maybe there’s a limited functionality 5.xx exploit on the horizon, but just a bit of reality before you get too excited.