By dropping it to X4, is that going to change the mining value of the card? I ask because if it helps miners, then they will flock to it like flies on... if it hinders the mining then gamers will have a nice reprieve from cards that will be scalped much higher than they are worth.
Most mining rigs run their GPUs in 2.0x1 perfectly fine. Mining requires almost no communications between the CPU and GPU other than telling the GPU which PRNG seed to start doing its block search from and updating the DAG when the block chain got a new block.
PCIe 4.0 x4 (equal to PCIe 3.0 x8) is not a problem, the RTX 3080 just starts to get bottlenecked at that and it's far more powerful.
Only because the RTX3080 has 10GB of VRAM, so it does not need to actively use system memory on an on-going basis to cover up its VRAM deficiency like 4GB and lower GPUs do when you want to push details slightly beyond what the VRAM can comfortably fit.
Being stuck on 3.0x8 was a huge problem for the 4GB RX5500 the instant games attempt to use more than 4GB. Having 4.0x8 allowed the 4GB models to close most of the gap with the 8GB models in those situations.
https://www.tomshardware.com/news/amd-rx-5500-xt-vram-pcie-4
In Far Cry: New Dawn, which is the most spectacular difference I have seen, the 4GB RX5500 roughly doubles its performance on 4.0x8 vs 3.0x8, bringing it practically on par with the 8GB models.
To me, it looks like AMD cripped the RX6500 to 4.0x4 to ensure the 4GB models will have absolutely no chance of shadowing possible 8GB variants by borrowing system memory.