This past weekend, Odyssey Team lead developer CoolStar successfully achieved read-only amfid task port on iOS & iPadOS 15.0-15.1.1. While this was obviously a terrific feat, jailbreaking requires both read and write, not just read.
CoolStar says read & write amfid task port achieved on iOS 15.0-15.1.1, up to and including A15 devices