FSs designed to run on dumb flash exist: https://encrypted.google.com/#q=site:lwn.net+nand+flash+file...

> I don't see why people try to design filesystems that do everything.

For general use, [0] I would rather use a FS that works on pretty much every media type [1] -and has reasonable perf- than to have to worry about whether $SPECIALTY_FS is actually tuned for $WEIRDO_BLOCK_DEVICE, or if I've failed to understand the particulars of either the FS, device, or both.

[0] That is, when getting the absolute best perf isn't a requirement.

[1] Except for like, tape, and optical RAM/WORM drives, natch.