Yeah, you can do some pretty wild things if you have direct access to the flash array. But then you need to handle stuff like wear leveling, transaction manage

Yeah, you can do some pretty wild things if you have direct access to the flash array. But then you need to handle stuff like wear leveling, transaction management, ECC and other forms of recovery. And a lot of the stuff you need to do is probably flash-part specific (e.g., read disturbance, probably stuff around channel management and throughput, etc.). I actually proposed allowing the firmware of a recent consumer product have such access to the flash (because I didn't trust the flash vendor's translation layer), but got shot down. I don't know how that turned out; probably they spent a bunch of time doing qualification (code for: "Fix your damned FTL bugs or we find another vendor. Wait. We don't have time for that. Fix as many as you can, or we'll be mad ... or something. Here, have some money.").