The 5800X3D has a (for now) unique gimmick that puts it in an awkward position. It's a halo-esque CPU in terms of price/being branded as "the fastest gaming CPU", but there are arguments to be made for both giving it god-tier RAM (as you, @freeagent, and others have said, to squeeze every drop of performance out of an expensive CPU), and for using cheaper RAM
The truth is... fast RAM is not really necessary for Ryzen CPUs, especially for gaming, p sure AMD still recommends "3000mhz" (which doesn't even work but 2933 works lol)
So what i was saying is if you really care about 5-10fps or so more then you should go for "fast" b-die / dr... but if you dont just get the cheapest RAM around 3000MHz, yes.
(thats besides i think this cpu is overpriced, at least in Europe and because of that in a *really* weird spot indeed)