I wouldn't say uClinux was any less Linux, over time its features even merged to mainline in the 2.x series, including the ability to run MMU-less in version 2.5.46 https://lwn.net/Articles/14823/
The EZ-Flash V 3-in-1 also had either 64 MB or 128 MB of NOR flash (depending on the revision) in addition to the 16 MB of PSRAM. There was also some battery backed SRAM for save data.
Is that PSRAM? For some reason I thought the bigger storage was Flash.