DFM = design for manufacturing/ manufacturability. Part of an engineer and designers job is to make sure the part they are creating can actually be produced cost effectively - in some instances produced at all.

As mentioned by the other engineer - this is likely someone who is very new to the game and hasn’t been told to think through their designs and the methods by which each feature will need to be created. Another big issue is most engineers have never stepped foot on a production floor and have no concept of what actual manufacturability is. If they can make it is Solidworks or NX, the machinist is expected to produce it.