I don't know Intel's reasoning for this policy, but if there's a sound technical reason for it, I would guess that it has to do with the drive not wanting to flush its NAND mapping information from DRAM to flash that it has deemed worn out. However, the Intel 335 Series uses SandForce controllers that don't have an external DRAM buffer, so they never have much data cached or in flight. It's more likely this policy was decided upon for enterprise products and was deemed not worth revising for client products given how few customers would exhaust the drive's write endurance to be affected by this.

EDIT: And, as pointed out by cuchulain, much of the information about the intended end-of-life behavior of Intel's SSDs is unreliable; they don't publish that information on a per-model basis, so some of what you read is based on mere speculation.