I recently purchased this

Dual PCIe 3.1 2.5GBase-T Network Adapter with Intel I225-V 2500/1000/100Mbps PCI Express Gigabit Ethernet NIC Card RJ45 LAN Controller for Windows 10/11 with Low Profile Bracket https://a.co/d/4PUQvFV

Just curious, digging into speeds. This says that it runs at PCIe 3.1 ( 5 GT/s ). My question is. Does that make any sense? 2.0/2.1 is 5GT/s and 3.0/3.1 is 8GT/s (all speeds are for x1 lane only.)

Is there some in-between where the card with run with the 3.0/3.1 overhead vs the 20% of 2.0/2.1 but only runs at 5GT/s instead of 8GT/s. Or is this utter bull$hit?