Some of the mixed-level specs refer to an NX derailleur – traditionally just below GX in the SRAM hierarchy. And some say just Eagle 70, which could be the OEM-only SX level? Interestingly ...

SX is the lowest tier of the SRAM 12-speed ... with its own prototype MTB derailleur and aftermarket support for SRAM MTB derailleurs, it showed that mechanical drivetrains are still relevant.