I seriously doubt any prospective buyer is actually looking at what's on offer and even has a second thought about PCIe 4.0 or 3.0. Its one of those things that is compatible anyway - if you worry about this, the last PC you built was something pre- PCIe 2.0. Bandwidth hasn't been an issue for decades.
Nvidia GPUs comparative to AMD's is a very different case. Here, AMD's CPU products are faster, draw less power and likely run cooler. I think that makes Intel's aging arch and older process node inferior to what AMD is using.
It is not a relevant metric when comparing products - you use the actual performance it gives and the characteristics it gives that under (power, heat), and in that sense, for 90% of use cases and people, these CPUs are virtually identical. At that point, the primary trigger becomes price - which is why Intel can still have an effect doing what they do now, even if by raw numbers the product 'is inferior' or 'on an inferior node'. The % of users that push a CPU to the limit is actually pretty low. Those who emphasize the need for CPU perf, know what they're looking for, so they dó notice it.
The thing that will really sell Ryzen 3 is the core count gap - its a very noticeable, visible way of telling buyers 'this one is better'. More cores at the same price. And the typical Intel safe haven of single thread dominance (clocks) is now gone too - another important number on the spec sheet.
Heck, its what AMD does with GPU - the problem there is that for gaming, GPUs are stressed constantly and not 'bursty' like CPUs tend to be, so people tend to notice the efficiency gap in a big way (more noise etc.) and load a GPU to cap much more often, which also highlights the performance gap.
