Why buy a new motherboard if there is no difference PCIe 4.0 vs 3.0 vs 2.0

[yomt38790]

why buy a new motherboard if there is no difference PCIe 4.0 vs 3.0 vs 2.0

why have a pcie 4.0 ? In practice, there is no difference between PCI-E 2.0
PCI Express version 2.0X16 8.0 GB/s
PCI Express version 3.0X16 15.75 GB/s
PCI Express version 4.0X16 31.51 GB/s

 

[Soulkeeper]

At some point in the future you might see a difference.
Once some faster cards come out, or textures/files get larger. The idea is that most hardware/software setups now aren't making pcie the bottleneck.
And each generation pci -> agp -> pcie 1 2 3 4 ... typically only show a few percentage points gains in any benchmarks. Even if speed doubles, you're only doubling the speed of one component of the system.

 

[Muadib]

You need to get a 4.0 Gen4 PCIe SSD drive to see the difference.