There can be. There are certainly Bios’ that don’t give options that motherboards are perfectly capable of changing. I had an old Phenom II that I managed to patch NVME support into the bios so I could boot off of a PCIe Riser.

Granted, I was patching UEFI stuff and none of it was open source – but the idea is the same. Open source bios in theory, could unlock features.