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 ...

the SRAM 70 sits at about the level of SX Eagle, and uses different materials to bring the price down to a more affordable pricepoint and will likely be found on more entry-level bikes. The derailleur ...

SRAM Transmission is no longer electronic-only. The new mechanical Eagle 90 & 70 versions might even shift faster!

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.