I can respect wanting the challenge to stay as is. I don't care if synths return as I don't need them, but this seems like it really wouldn't affect your sense of challenge and accomplishment unless you use it. Would others using ammo synth truly bother you that much? I mean, they're only ruining it for themselves from your perspective. Unless they're in your fireteam, that is. (Disclaimer: I'm honestly just asking to clarify your view. Not here to argue for anything.)