> vfat won because it works in Windows without additional drivers.
I would not understate that it is also very simple to write a driver for. The reasons for this have high overlap with the fact that the ondisk structure is crap. But it does mean that many people were able to write drivers.
I wrote a driver for it on an 8-bit chip that had 16kB of code space and 2kB of RAM. It was ugly, and it could only hold two sectors at a time in memory (if I recall, one from the FAT and one from the current file). Despite it being ugly... it worked! Best of luck getting pretty much any other standard filesystem running in that.
