You could put spinning HDDs in your laptop, but the heat generated dictates how small the chassis can be...32GB presents the same challenges. Back in 2012, DDR3-1600, but you need 4x8GB, since 16GB SO-DIMM came on board closer to late 2015 or even early 2016, IIRC. Again, space for 2 to 4 DIMM sockets plus the heat generated by 4 SO-DIMMs dictates a larger chassis and more robust cooling system, so did most CPUs of that day and even now in the age of 6-core 45w CPUs, heat is an issue. You mentioned compact, which all of these desired features work against. Not to mention the battery and PSU for a laptop to meet your needs would last less than two hours on battery and require a 300w brick to power.
NAND is just now getting to an acceptable place with regard to speed, heat, capacity and cost. Intel has still not followed through and brought us to LPDDR4/x, making us wait until Cannon Lake, which is completely absurd and reeks of pre-planned obsolescence, but I digress. CPUs forge ahead, but only so much can be put inside a 45w-65w TDP.
Your path is unique and difficult and not one Apple will ever be able to fulfill. Good luck!