There appears to be a sea change in RAM (on a Macbook) and its affect on the price. I remember I bought a Mac Book pro back in 2009, and while the upgrade to 4gb was $200, the upgrade to 8gb was $1000 IIRC! Whereas the upgrade from 32GB to 64GB was only $400 here.
Back then, more memory required higher density chips, and these were just vastly more expensive. It looks like the M1 Max simply adds more memory controllers, so that the 64GB doesn't need rarer, higher priced, higher density chips, it just has twice as many of the normal ones.
This is something that very high and laptops do: have four slots for memory rather than two. It's great that Apple is doing this too. And while they aren't user replaceable (no 128Gb upgrade for me), they are not just more memory on the same channel either: the Max has 400GB/s compared to the Pro 200Gb/s.
Back then, more memory required higher density chips, and these were just vastly more expensive. It looks like the M1 Max simply adds more memory controllers, so that the 64GB doesn't need rarer, higher priced, higher density chips, it just has twice as many of the normal ones.
This is something that very high and laptops do: have four slots for memory rather than two. It's great that Apple is doing this too. And while they aren't user replaceable (no 128Gb upgrade for me), they are not just more memory on the same channel either: the Max has 400GB/s compared to the Pro 200Gb/s.