It's laughable how gullible PC enthusiasts can be...
There is absolutely no need for or advantage to having DDR4 and PCIe 4 on a current model desktop regardless of what CPU/APU it has. DDR4 is primarily for server use. It will be expensive, impractical for most desktop PCs and not offer any real advantage over LV DDR3 on the desktop.
PCIe 3.0 isn't even being widely used yet because PCIe 2.1 isn't a system limitation. More bandwidth on a system that isn't bandwidth limited makes no system performance gain.
All of this crap is marketing hype to try and boost sagging PC sales. It doesn't cost mobo makers more than a few pennies if that to use future standards that offer no real system performance gains. This allows the mobo makers to hype the future tech, charge even more excessive prices and the sheeple will spend their money like drunken sailors.
One answer for all of your "sheeple" issues.
ODT
On Die Termination.
For memory operating at a significantly higher voltage than die traces can handle, meaning we either have to perform extra steps during manufacturing, or create more traces to dump the voltage.
For PCIe, most of the same reasons listed above.
For all other interconnects, see above.
When all Intel or AMD had to do was create a chip and the NB handled the voltage power differences, termination, and much else it wasn't an issue. However now that it is on die it is becoming much more difficult to maintain signal integrity at lower voltages while assuring reliability with multiple manufacturers of memory, motherboards, PCIe devices.
Add to this idea that if AMD has figured out heterogeneous memory, Intel is surely on the same path and as we approach the efficiency limit in processing serial data and find parallel falling behind without a "co-processor" added on that needs higher speed memory access we find the need to make the next jump in performance to occur.
In short, the people you are calling people sheeple in a vain attempt to cover your lack of knowledge know what and why this is needed, so not only do you look like a dick, but a stupid dick.