" I came across one that stated it did require a minimal amount of RAM."
An SRAM sized to one read write block of the flash....note this is not an erase block(or array)
SRAM(transistor) is not the same as DRAM(charged capacitor) and is much more expensive, however, they only need a tiny amount.
They do not shadow whole files to it as you would with DRAM or SDRAM. They page tiny bits to it, where if you pull the flash out, the bit stream stops.
In the end they will own this process industry wide where it all leans on direct discrete manipulation as you commented.
doni