Ridiculous and false reasoning. Had they used LPDDR4 instead of LPDDR3 they could have stuck 32GB in that machine at an even lower voltage level.
EDIT:// Also Samsung is selling LPDD4x a new off-shoot which goes down to 0.6v (compared to 1.2v of LPDDR3 and 1.1v of LPDDR4). They definitely could have got some from Samsung but chose not to.
The CPU used in these computers supports both DDR3 and DDR4 and the Samsung LPDDR4x is materially identical to LPDDR4 in compatibility, it just lowers I/O voltage.
Doesn't DDR4 increase latency? At least that is my takeaway from some reading.