EATX is a pretty standard server motherboard form factor.

It's not even a multiple CPU board...

This is indeed a pretty standard (and weak) ARM server build.

You can get the same CPU M128-30 with 128 3ghz cores for under $800 USD.

You can throw two into a Gigabyte MP72-HB0 and fit it into a full tower case easily.

That'd only cost like $3,200 USD for 256 cores.

RAM is cheap, and that board could take 16 DIMMs.

If you used 16 GB DIMM like OP that's only 256 GB of RAM, in a server, it is not that much... only one gig per core... for like $500 USD.

Maybe for a personal build this seems extravagant but it's nothing special for a server.