The boards using LPDDR don't have socketed CPUs. Also, every connector is a huge hit to your signal integrity, so one versus two might indeed be a big deal.

And yeah, it can be, but that's how you end up with the far slower regular DDR. Fast, repairable, cheap: pick (at most) two.

No, even in multiple RAM channel Server, the CPU is still socketed. That means all the data is going through a socket before reaching the CPU.

I agree there is draw back when using socket(mostly size), but performance is not the big issue.

MRDIMM RAM can reach even higher Transfer rate than LPDDR5, yet still socktable.