Many people don't want to bother with OCing and the likelihood of getting screwed over by the silicon lottery, especially on Zen 2 where manual OC is often worse than stock in workloads that benefit more from automatic few-cores boost. Also, since AMD likely bins dies for those new SKUs, lower-end parts may very well end up with demonstrably worse silicon on average than before.
And how would you demonstrate "demonstrably"? AMD chips starting to fail at stock? Or ... Chips that don't OC anywhere near their boost clocks in most cases, just like now, except not doing that ... more??
Those are about your only two options there, and the 2nd one is moot, and the 1st one isn't reasonable.
It would be far more likely that AMD is running into an excess of better silicon now that the production has had a full year to mature, so might as well capitalize on that by putting the CCXs that are fully capable of being 3950Xs, but the demand for that chip <> the quantity of good silicon, therefore, use those CCXs to create new lower core count skus -- the more popular ones ...
I don't buy the idea that AMD is only doing this to counter Comet lake .... they don't really need to counter with zen3 right around the corner, so to me, the idea of just trying to utilize the best silicon in the way that will make them sell more of that high quality silicon, and maybe get a little better premium ... that makes the most sense to me.
I still don't think the price should exceed the launch prices for their original counterparts, that would be a fail, if they did, in my opinion.