I'm writing this on a four-year-old Macbook Pro and it only has 16 GB of RAM. Server-class machines would still need to address more memory than that, but they're usually running specialized software or virtualizing; databases and hypervisors are already tricky code and segmentation wouldn't be the end of the world.

Because, I have a ten year old Dell laptop with 40GB of RAM, 16GB seems like an arbitrary limitation, an engineering compromise, or something like that.

I don’t see how it is a result of 8 bit bytes because 64bits has a lot of address space.

And because my laptop is running Windows 10 currently and ram Ubuntu before that, ordinary operating systems are sufficient.

—-

Also ECC RAM is 9 bits per byte.