With RAM, the problem is more that high capacity LPDDR4 modules simply aren't available on SODIMMs.
However this is only because manufacturers don't make them. If Apple asked Micron or Samsung for them, I'm sure it would happen.
A better argument for non-replaceable RAM can be found in the Apple Silicon chips. Building the memory into the SoC provides very tangible performance and efficiency benefits.
>With RAM, the problem is more that high capacity LPDDR4 modules simply aren't available on SODIMMs.
And I don't think they ever will be. From the little bit that I've read, the higher voltage that SODIMMs have to use has to do with noise in transmission. LPDDR4s have been connection through the direct solder, so are able to use lower voltages.
I'm not an electrical engineer but I have a hard time believing we can't design a socket that provides a connection as stable and free from interference as a solder joint. It could mean making a PGA or LGA socket similar to what we use for CPUs, but it should still be perfectly doable.
However this is only because manufacturers don't make them. If Apple asked Micron or Samsung for them, I'm sure it would happen.
A better argument for non-replaceable RAM can be found in the Apple Silicon chips. Building the memory into the SoC provides very tangible performance and efficiency benefits.