Some vendors still have a red flag on their support page discouraging uefi updates unless you're actively experiencing problems.
I dont know which vendor you are referring to, but that is a horrible practice. There should be active support and release notes stating that "This release is a security fix" at a bare minimum. If your motherboard manufacturer does not offer that, then I could never recommend them to someone. They need to be held to a higher standard.
At least from my experience, ASUS, Dell, and Apple will publish that information.