What should a motherboard like this have? I think the W680 is a good place to start and an ATX with more PCIE slots. 1x 16/ 8/8 5.0 that support bifurcation, 2x or more 4x4 4.0. 2 M.2 5.0 and 2 M.2 4.0. ECC. 5gb nic onboard.
Can that be made with the current AMD chipsets, or would it require new chips?
What do the future bring when home servers move to SDD for main storage and when will it happen?
This should serve a normal family with media/storage and have pcie connections, to keep the versatility/make it future-proof.
Work with win, linux & proxm.
Ideally, iGPUs that have as good video support as Intels UHD 770, so it can transcode without a GPU, eg with very low energy use & idle.
This below from Supermicro is close but lacks bifurcation and is not ATX. I don’t mind paying 600$ if it has the full features I need, but all come short.
I noticed @wendell also mentioned this in his videos about home servers/WS, with a board with more pcie slots. 
Intel had done away with OC in W880 due to segmentation, which is fine for me. Its a server.
AMD should do it to offer a better alternative to Intels WS x80 boards, than high-end gaming boards, which cost a lot, but do not fulfill all the requirements, but only some while still having a lot of for a server unnecessary bling. AMD has the best CPUs this time and their platform’s longevity makes investing more in the motherboard a better investment, but the motherboards are expensive while they still don’t tick all the boxes. The Taichi does not have the PCI-E slots.
https://www.newegg.com/supermicro-mbd-h13sae-mf-o-amd-ryzen-7000-series/p/N82E16813183830