Does this notion fall afoul of 406.4(B)? You are not talking about a replacement, which would be covered by 406.4(D).
But now speaking as a homeowner in answer to the original question, I get upset when I look at a box and see that the EGC conductor has been clipped. What if I wanted someone to upgrade the circuit by connecting the EGC at the outlet and finding a way to connect it (however indirectly) to the ground bar in the panel? 250.130(C) offers several options for accomplishing this. A clipped wire would not allow that connection to be made.
That concept is what got me thinking about whether to clip or not clip...
Currently I’m working in a house that has mostly 2-wire circuits. Most of what I’m doing is changes related to lighting circuits.
As I was working, running new NMB, I was debating about the idea of somewhere down the road if someone wanted to upgrade the circuit to I grounded circuit I’m just making things harder for that person.
On the other hand, I can’t imagine how involved it would be to go through a house and upgrade the lighting circuits to grounded unless it was a total gut and started from scratch!