Joint Tactical Information Distribution System - Wikipedia
PCIe 4.0 SSDs can only match the speeds of a PCIe 4.0 slot, and PCIe 3.0 SSDs can't leap in data transfer rate and bandwidth to PCIe 4.0.
Can I Use a PCIe 3.0 Card in a 2.0 Slot? - PC Guide 101
A PCIe 4.0 NVMe SSD will work in a PCIe 3.0 M.2 motherboard slot at PCIe 3.0 speeds.
ASUS ROG STRIX B760-I GAMING WIFI iTX Mainboard
Intel ® 13th & 12th Gen Processors 1 x PCIe 5.0 x16 slot(s) Intel ® B760 Chipset 1 x PCIe 4.0 x16 slot (supports x4 mode) 2x PCIe 4.0 x1 slots.