I remember in 2007, buying my first MacBook. It came with an enormous 2gb of RAM. I asked about upgrading it. The guy leaned in conspiratorially and told me that Apple’s RAM upgrades were a rip-off, and that I’d be better of buying it elsewhere. So I did, for half of what Apple were asking.
This is a grift that Apple have had for far too long, and there’s a part of me that’s convinced that their move to soldered RAM was to stop people upgrading after the fact more than it was about SOC efficiencies.
The boards are already in production by some company iirc. Dosdude1 on YouTube did some upgrades on various M series machines
The boards that dosdude1 used are specific to Mac Studio. The mini M4 and M4 pro model each use their own unique nand board.
I see. Which is unfortunate but at least there’s a starting point