The XOR scheme is perfectly good enough. If it were a real issue affecting customers it would be replaced (but it isn't).
The XOR scheme is extremely cheap (compact) and does not need to operate serially on the data stream (good for performance). The only applications that use the NAND provided randomizer are the cheapest of controllers. In fact, even the SD controller in the linked article used their own XOR scheme. A system designer can always turn off the builtin randomizer, and replace it with whatever method they choose -- they all do for various reasons. At the controller level it can be implemented in, typically, higher performance and more compact logic processes. It does not need to be duplicated for multichannel devices, as it would if it were in the NAND.
...until someone finds a way to exploit it, as has happened with CD's "weak sector" copy protection schemes. It's only a matter of when it will happen, not if.
Corrupting the storage of a test pattern isn't particularly useful. MAYBE, you could cause premature tagging of bad blocks wearing out a flash drive/card faster. If the system you are using is allowing these kinds of writes to your storage device you have more pressing issues.
Only the most primitive SD/flash drive controllers actually use this scheme anyway -- encryption is much better at randomizing.
The XOR scheme is extremely cheap (compact) and does not need to operate serially on the data stream (good for performance). The only applications that use the NAND provided randomizer are the cheapest of controllers. In fact, even the SD controller in the linked article used their own XOR scheme. A system designer can always turn off the builtin randomizer, and replace it with whatever method they choose -- they all do for various reasons. At the controller level it can be implemented in, typically, higher performance and more compact logic processes. It does not need to be duplicated for multichannel devices, as it would if it were in the NAND.